Practice Test

Q1) Cathode rays are Show Answer

Q2) Which is not true respect to cathode rays ? Show Answer

Q3) Number of neutron in heavy hydrogen atom is Show Answer

Q4) The orbit in Rutherford's model is Show Answer

Q5) The credit of discovering neutron goes to Show Answer

Q6) The mass of the neutron is of the order of Show Answer

Q7) Atomic number is equal to the Show Answer

Q8) What is the packet of energy called ? Show Answer

Q9) Which of the following does not characterise X - rays? Show Answer

Q10) Threshold energy is also called Show Answer

Q11) Frequency of matter wave is equal to Show Answer

Q12) An electron in H-atom in its ground state absorbs 1.50 times as much as energy as the minimum required for its escape ( 13.6 eV) from the atom. Thus kinetic energy given to emitted electron is Show Answer

Q13) Visible spectrum extends from 400 nm (violet) to 750 nm (red). Hence frequency ratio is Show Answer

Q14) The accelerating potential that must be imparted to a proton beam to give it an effective wavelength of 0.05 nm is (wt. of proton = 1.008 g) Show Answer

Q15) Heaviest particle is Show Answer

Q16) Rutherford's scattering experiment is related to the size of the Show Answer

Q17) When alpha particles are sent through a thin metal foil most of them go straight through the foil because Show Answer

Q18) Electromagnetic radiation with maximum wavelength is Show Answer

Q19) Rutherford's alpha rays scattering experiment eventually led to the conclusion that Show Answer

Q20) Rutherford's experiments, which established the nuclear model of the atom, used a beam of Show Answer

Q21) As we move away from nucleus, the energy of orbit Show Answer

Q22) The radius of the atom is of the order of Show Answer

Q23) 1 erg of energy corresponds to Show Answer

Q24) Sodium chloride imparts a yellow colour to the Bunsen flame. This can be interpreted due to the Show Answer

Q25) With increasing principal quantum number, the energy difference between adjacent energy levels in H atom Show Answer

Q26) Splitting of spectral lines under the influence of magnetic field is called Show Answer

Q27) The first emission line in the atomic spectrum of a hydrogen in the Balmer series appears at Show Answer

Q28) The r is the radius of first orbit, the radius nth orbit of the H atom will be Show Answer

Q29) The electron in an atom Show Answer

Q30) The value of Planck's constant is Show Answer

Q31) Who modified Bohr's theory by introducing elliptical orbits for electron path ? Show Answer

Q32) The third line of the Balmer series, in the emission spectrum of the hydrogen atom, is due to transition from the Show Answer

Q33) As the nuclear charge increases from neon to calcium, the orbital energies Show Answer

Q34) The energy of the first electron in helium will be Show Answer

Q35) In the Bohr's orbit, what is the ratio of total kinetic energy and total energy of the electron ? Show Answer

Q36) The radius of second Bohr's orbit is Show Answer

Q37) The energy of hydrogen atom in its ground state is -13.6 eV.The energy of the level corresponding to the quantum number n = 5 is Show Answer

Q38) For the energy level in an atom, which one of the following statements is correct ? Show Answer

Q39) According to Bohr's theory, the energy required for the transition of H atom from n=6 to n=8 state is Show Answer

Q40) The value of the energy for the first excited state of hydrogen will be Show Answer

Q41) Time taken for an electron to complete one revolution in the Bohr orbit of hydrogen atom is Show Answer

Q42) In hydrogen atom, energy of first excited state is -3.4 eV. Find out the K. E. of the same orbit of hydrogen atom. Show Answer

Q43) The one electron species having ionisation energy of 54.4 eV is Show Answer

Q44) What is the number of revolutions of an electron in second Bohr's orbit of H-atom in one second ? Show Answer

Q45) What is the angular momentum of H-atom orbit if its electron energy is -3.4 eV ? Show Answer

Q46) If the electron in a hydrogen atom drops from the n = 6 to the n = 4 level, the radiation emitted is in which series of lines in the spectrum of atomic hydrogen ? Show Answer

Q47) Angular momentum of an electron in the n th orbit of hydrogen atom is given by Show Answer

Q48) In a hydrogen atom, if the energy of an electron in the ground state is 13.6 eV, then that in the 2 nd excited state is Show Answer

Q49) Bohr's model can explain Show Answer

Q50) If the speed of electron in Bohr's first orbit of hydrogen atom be x, then speed of the electron in 3rd orbit is Show Answer

Q51) The energy of an electron in the first Bohr's orbits of H atom is -13.6 eV.The possible energy value (s) of the excited state (s) for electron in Bohr's orbits of hydrogen is (are) Show Answer

Q52) The radius of which of the following orbits is same as that of the first Bohr's orbit of hydrogen atom ? Show Answer

Q53) Which of the following expressions gives the de Broglie relationship ? Show Answer

Q54) If uncertainty in the position of electron is zero, the uncertainty in its momentum would be Show Answer

Q55) The de-Broglie wavelength of a particle with mass 1 g and velocity 100 m/s is Show Answer

Q56) Uncertainty in position and momentum are equal. Uncertainty in velocity is Show Answer

Q57) If the radius of first Bohr orbit is x, the de-broglie wavelength of electron in 3 rd orbit is nearly Show Answer

Q58) The uncertainty principle and the concept of wave nature of matter was proposed by....... and ..... respectively Show Answer

Q59) The de-Broglie wavelength of a tennis ball of mass 60 g moving with a velocity of 10 metres per second is approximately Show Answer

Q60) Which of the following relates to photons both as wave motion and as stream of particles ? Show Answer

Q61) The wavelength associated with a golf ball weighing 200 g and moving at a speed of 5 m /h is of the order Show Answer

Q62) The magnetic quantum number represents Show Answer

Q63) The principal quantum number, n describes Show Answer

Q64) Subsidiary quantum number specifies Show Answer

Q65) No two electrons in an atom will have the four quantum numbers same. This statement is known as Show Answer

Q66) "The exact path of electron in 2p-orbital cannot be determined". The above statement is based upon Show Answer

Q67) No two electrons in an atom can have Show Answer

Q68) Azimuthal quantum numbers determines the Show Answer

Q69) In a set of degenerate orbitals the electrons distribute themselves to retain similar spin as far as possible. This statement is attributed to Show Answer

Q70) The total number of orbitals in a shell with principal quantum numbers 'n' is Show Answer

Q71) The electronic configuration of an atom / ion can be defined by the following Show Answer

Q72) Which of the following orbitals have a dumb-bell shape? Show Answer

Q73) A 4f orbital has Show Answer

Q74) The number of electrons in the M Shell of the elements with atomic number 24 is Show Answer

Q75) The electron present in K-Shell of the atom will differ in Show Answer

Q76) For a given principal level n = 4, the energy of its sub -shell is of the order Show Answer

Q77) The maximum number of electrons in a sub shell is given by the expression Show Answer

Q78) An electron has pricipal quantum number 3. The number of it's (i) subshells and (ii) orbitals would be respectively? Show Answer

Q79) Which of the following has same number of electrons in the last shell? Show Answer

Q80) The maximum number of electrons in a subshell for which l = 3 is Show Answer

Q81) The quantum numbers for the after electrons of an atom are given by n = 2; l = 0; m = 0; s = 1/2. The atom is Show Answer

Q82) The maximum number of electrons in p-orbital with n = 6; m = 0 is Show Answer

Q83) Indicate which electronic configuration amongest the following correcltly represents the sulphur atom ? Show Answer

Q84) Which quantum number is sufficient to describe the electron in hydrogen atom ? Show Answer

Q85) When the azimuthal quantum number l=1, the shape of the orbital will be Show Answer

Q86) Which one of the following shows the correct electronic configuration of the outermost shell in insert gases ? Show Answer

Q87) The correct set of quantum numbers for the unpaired electron of chloride atom is Show Answer

Q88) The valence orbital configuration of an element with atomic number 23 is Show Answer

Q89) Which of the following electronic configurations is not possible ? Show Answer

Q90) Electronic configuration of calcium atom can be written as Show Answer

Q91) Which of the following sets of quantum numbers is not possible ? Show Answer

Q92) An electron has a spin quantum number +1/2 and a magnetic quantum number -1. It cannot be present in Show Answer

Q93) The set of quantum number not applicable to an electron is Show Answer

Q94) The quantum number values for the designation 3 d are Show Answer

Q95) For which of the following sets of quantum numbers an electron will have the highest energy ? Show Answer

Q96) Which of the following has more unpaired d-electrons ? Show Answer

Q97) The correct set of quantum numbers for 4d-electrons is Show Answer

Q98) The ground state electronic configuration of chromium is Show Answer

Q99) Which of the following represents noble gas configuration ? Show Answer

Q100) The number of electrons in 3d shell for element with atomic number 26 is Show Answer

Q101) The total number of possible values of magnetic quantum number for the value of l = 3 is Show Answer

Q102) Which one of the following pairs of atoms / atom - ion have identical ground state configuration ? Show Answer

Q103) If the value of principal quantum number is 3, the total possible value for magnetic quantum number will be Show Answer

Q104) The number of spherical nodes in 3p orbitals are Show Answer

Q105) The four quantum numbers of the valency electron of potassium are Show Answer

Q106) In which of the following pairs, the number of electrons in the outermost shell are different ? Show Answer

Q107) Electronic configuration of most electronegative element is Show Answer

Q108) Which of the following sets of quantum numbers belongs to highest energy ? Show Answer

Q109) For how many orbitals, the quantum numbers n = 3, l = 2, m = +2 are possible ? Show Answer

Q110) The nineteenth electron of chromium has which of the following set of quantum number ? Show Answer

Q111) The correct order of increasing energy of atomic orbitals is Show Answer

Q112) Number of orbitals present in 3rd shell is Show Answer

Q113) The atomic number of an element is 35. What is the total number of electrons present in all the p-orbitals of the ground state atom of that element? Show Answer

Q114) An element M has atomic mass 19 and atomic number 9.It's ion is represented by Show Answer

Q115) Which of the following is not isoelectronic? Show Answer

Q116) The total number of electrons present in all the s-orbitals, all the p-orbitals and all the d-orbitals of cesium ion are respectively Show Answer

Q117) In the ground state, an element has 13 electrons in its M shell. The element is Show Answer

Q118) Which of the following ions has the maximum magnetic moment? Show Answer

Q119) Which of the following electronic configurations is not possible according to Hund's rule ? Show Answer

Q120) One of the following pairs of ions have the same electronic configuration ? Show Answer

Q121) Two electron in the same atomic orbital can be distinguished by their Show Answer

Q122) Which of the following element's outermost orbits last electron has magnetic quantum number m = 0 ? Show Answer

Q123) Among the following series of transition metal ion, the one where all metal ions have same 3d electronic configuration is Show Answer

Q124) For d- electron, the orbital angular momentum is Show Answer

Q125) Find the magnetic moment of a divalent ion in aqueous solution if its atomic number is 25 Show Answer

Q126) The atomic numbers of elements X, Y and Z are 19, 21 and 25 respectively. The number of electrons present in the 'M' shells of these elements follow the order Show Answer

Q127) which of the following arrangements of electrons is most likely to be stable ? Show Answer

Q128) Hund's rule deals with the distribution of electrons in Show Answer

Q129) Chloride ion and potassium ion are isoelectronic. Then Show Answer

Q130) For f-orbital, the values of m are Show Answer

Q131) Correct energy value order is Show Answer

Q132) The highest number of unpaired electrons are present in Show Answer

Q133) Consider the ground state of Cr atom (Z = 24). The numbers of electrons with the azimuthal quantum numbers l = 1 and l = 2 are respectively. Show Answer

Q134) Which of the following sets of quantum numbers is correct for an electron in 4 f - orbital ? Show Answer

Q135) Which of the following statements in relation to the hydrogen atom is correct ? Show Answer

Q136) In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic field and electric fields ?
(A) n = 1, l = 0, m= 0
(B) n = 2, l = 0, m= 0
(C) n = 3, l = 1, m= 1
(D) n = 3, l = 2, m = 1
(E) n = 3, l = 2, m= 0 Show Answer

Q137) Which of the following has non - spherical sub - shell of electron ? Show Answer

Q138) The principal quantum number of an atom is related to the Show Answer

Q139) Any p-orbital can accommodate up to Show Answer

Q140) The electron level which allows the hydrogen to absorb photons but not to emit is Show Answer

Q141) Which one of the following sets of quantum number represents an impossible arrangement ? Show Answer

Q142) The correct of quantum numbers for the unpaired electron of Cl atom is Show Answer

Q143) The quantum number not obtained from the Schrodinger's wave equation is Show Answer

Q144) The outer shell configuration of the most electronegative element is Show Answer

Q145) Which combination of quantum numbers n, l, m, s for the electron in an atom does not provide a permissible solution of the wave equation ? Show Answer

Q146) Which of the following is violation of Pauli's exclusion principle ? Show Answer

Q147) From the given sets of quantum numbers the one that is inconsistent with the theory is Show Answer

Q148) Which of the following has maximum number of unpaired electron ? Show Answer

Q149) The electron identified by quantum number n and l,
(i) n = 4, l = 1 (ii) n = 4, l = 0 (iii) n = 3, l = 2 (iv) n = 3, l = 1
can be placed in order of increasing energy, from the lowest to highest, as Show Answer

Q150) The quantum numbers +1/2 and -1/2 for electron spin represents Show Answer

Q151) Identify the least stable among the following. Show Answer

Q152) How many structures of F are possible ? Show Answer

Q153) Radial nodes present in 3s and 2p-orbital are respectively. Show Answer

Q154) The ionization potential of hydrogen from ground state to the first excited state is Show Answer

Q155) The mass of proton is 1840 times of electron, its potential difference is 1 kV. The kinetic energy of proton is Show Answer

Q156) The presence of 3 unpaired electrons in N atom can be explained by Show Answer

Q157) A cricket ball of 0.5 kg. is moving with a velocity of 100 m/sec. The wavelength associated with its motion is Show Answer

Q158) The number of radial nodes in 5d is Show Answer

Q159) The H-spectrum shows Show Answer

Q160) Which of the following statements does not form a part of Bohr's model of hydrogen atom ? Show Answer

Q161) Electrons will first enter into the set of quantum numbers n = 5, l = 0 or n = 3, l = 2 Show Answer

Q162) Which of the following is non - permissible ? Show Answer

Q163) The following quantum numbers are possible for how many orbitals ? n =3, l = 2, m = +2. Show Answer

Q164) In Bohr series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inter-orbit jumps of the electron for Bohr orbits in an atom of hydrogen ? Show Answer

Q165) Which of the following is correctly matched ? Show Answer

Q166) In which of the following orbital diagrams are both Pauli's exclusion principle and Hund's rule violated ? Show Answer

Q167) Which of the following sets of quantum numbers represents the highest energy of an atom ? Show Answer

Q168) Nucleus of an atom was discovered by Show Answer

Q169) Discharge tube experiments demonstrate the emission of certain invisible rays from Show Answer

Q170) Cathode rays were named as electrons by Show Answer

Q171) Cathode rays have Show Answer

Q172) Protons were discovered by_______ Show Answer

Q173) Which statement is WRONG about anode rays? Show Answer

Q174) Which of the following statement is wrong? Show Answer

Q175) The charge to the mass ratio [e/m] of positive particles Show Answer

Q176) The mass of a neutron is Show Answer

Q177) Neutrons are present in all atoms except Show Answer

Q178) Atomic number of an element is equal to the number of Show Answer

Q179) The number of electrons and neutrons of an element is 18 and 20 respectively. Its atomic mass is Show Answer

Q180) Which scientists showed that atomic number represents the number of protons in the nucleus of an atom? Show Answer

Q181) The atomic weight and atomic number of an element are A and Z respectively. The number of neutrons in the atom of that element is calculated as Show Answer

Q182) The introduction of a neutron into the nucleus of an atom would lead to a change in Show Answer

Q183) Which of the following has same position in periodic table? Show Answer

Q184) The postulate that all the atoms of an element are exactly alike was proved wrong with the discovery of Show Answer

Q185) Antoine Becquerel proved that atoms are divisible with the help of his famous discovery of Show Answer

Q186) When alpha particles are sent through a thin metal foil, most of them go straight through the foil because Show Answer

Q187) Who discovered the nucleus of an atom? Show Answer

Q188) Rutherford's experiment established that Show Answer

Q189) The wavelength of a spectral line for electron transition is inversely related to Show Answer

Q190) The phenomenon of splitting of spectral lines under the influence of the magnetic field is known as Show Answer

Q191) When an electron jumps from lower energy level to higher energy level Show Answer

Q192) In which case, the wavelength of the radiation emitted will be minimum? Show Answer

Q193) Bohr's orbits are called stationary orbits because Show Answer

Q194) Which one of the following statement is incorrect? Show Answer

Q195) When electrons revolve in stationary orbits, Show Answer

Q196) Which among the following transition will give Lyman series in the hydrogen line spectrum? Show Answer

Q197) The spectral line obtained when an electron jumps from n= 6 to n= 2 level in hydrogen atom belongs to the Show Answer

Q198) Which of the corresponding regions of the spectral lines of hydrogen atom is not correct? Show Answer

Q199) Bohr model of atom can explain Show Answer

Q200) Brackett series are produced when the electrons from the outer orbits jump to Show Answer

Q201) According to Bohr's atomic model, P shell contains_______ electrons. Show Answer

Q202) The dual nature of radiations was proposed by Show Answer

Q203) Which of following is not a characteristic of Planck's quantum theory of radiation? Show Answer

Q204) Which of the following statement concerning light is false? Show Answer

Q205) According to de Broglie equation, wavelength of electron is Show Answer

Q206) The de-Broglie equation suggests that an electron has Show Answer

Q207) Heisenberg's uncertainty priciple rules out the exact simultaneous measurement of Show Answer

Q208) A region in space around the nucleus of an atom where the probability of finding an electron is maximum is called Show Answer

Q209) The quantum number not obtained from the solution of Schrodinger wave equation is Show Answer

Q210) The probability of finding an electron at the nucleus is Show Answer

Q211) Which of the following sets of quantum number is not possible for 23rd electron of Cr (At. No. 24)? Show Answer

Q212) How many quantum numbers are required to define the electron in atom? Show Answer

Q213) The possible subshells in n = 3 energy shell are Show Answer

Q214) The principal quantum number n describes the Show Answer

Q215) The angular momentum of an electron in atomic orbital depends upon the Show Answer

Q216) The total number of orbitals in the fifth energy level is Show Answer

Q217) To give a designation to an orbital, we need Show Answer

Q218) The designation of a subshell with n= 4 and l= 3 is Show Answer

Q219) 2p orbitals have Show Answer

Q220) The two electrons present in an orbital are distinguished by Show Answer

Q221) The value of azimuthal quantum number for electrons present in 4p - orbitals is Show Answer

Q222) If the value of azimuthal quantum number of an electron is 2, then which of the following value of magnetic quantum numbers is not permissible? Show Answer

Q223) If m has seven values, the value of azimuthal quantum number should be Show Answer

Q224) The azimuthal quantum number is related to Show Answer

Q225) Principal, azimuthal and the magnetic quantum numbers are respectively related to Show Answer

Q226) Magnetic quantum number gives Show Answer

Q227) Principal quantum number describes the Show Answer

Q228) Which of the following orbitals does not exist? Show Answer

Q229) How many electrons can have n = 4 and l = 2? Show Answer

Q230) The maximum number of electrons in p-orbital with n = 6, m = 0 is Show Answer

Q231) The electrons present in K-shell of the atom will differ in Show Answer

Q232) Value of l = 1 represents________ Show Answer

Q233) The maximum number of electrons in s, p and d- subshells are Show Answer

Q234) In s orbital as the value of n increases, the size of the s orbital Show Answer

Q235) Which shape is associated with the orbital designated by n = 2, l = 1? Show Answer

Q236) The shape of the orbital with the value of l = 2 and m = 0 is Show Answer

Q237) For a dumb-bell shaped orbital, the value of l is Show Answer

Q238) The order of filling of electrons in the orbitals of an atom will be Show Answer

Q239) The shape of s- orbital is Show Answer

Q240) All ________ orbitals are non- directional and spherically symmetrical. Show Answer

Q241) when 3d orbitals are completely filled, new electron will enter in Show Answer

Q242) What do you mean by degenerate orbitals? Show Answer

Q243) Hund's rule deals with the distribution of electrons in Show Answer

Q244) The Aufbau principle implies that a new electron will enter an orbital for which Show Answer

Q245) The number of unpaired electrons in chromium ( Z=24) is Show Answer

Q246) The tendency of an electron to exchange energy is _______ when the subshell is either half filled or completely filled. Show Answer

Q247) According to Dalton's theory, atoms of different elements Show Answer

Q248) Canal rays is a beam of Show Answer

Q249) Electrons, protons and neutrons are known as ________ particles of atom Show Answer

Q250) The electrons placed in the different shells of an atom of an element are… K-shell: 2 electrons, L-shell: 8 electrons, M-shell: 4 electrons. The atomic number of the element is Show Answer

Q251) which of the following is the correct statement for isotopes? Show Answer

Q252) J. J Thomson proposed that an atom has ______ shape. Show Answer

Q253) Which of the following statement about spectral series is incorrect? Show Answer

Q254) The maximum number of electrons in f- subshell is Show Answer

Q255) The photoelectric emission from a surface starts only when the light incident upon the surface has a certain minimum Show Answer

Q256) The total number of subshell in the 4th shell is Show Answer

Q257) Which of the following statement regarding the probability of finding the electron in p-orbital is wrong? Show Answer

Q258) Stability of completely filled and half filled subshell can be explained on the basis of Show Answer

Q259) Experiments revealing that atom is composed of fundamental particles rejected_________model of atom. Show Answer

Q260) Which of the following statements about quantum numbers is wrong?
Show Answer

Q261) The conclusion that an orbital can accommodate only two electrons is derived from
Show Answer

Q262) ______ principle limits the number of electrons in any orbital of an atom.
Show Answer

Q263) " The exact path of electron in 2p-orbital cannot be determined". This statement is based upon
Show Answer

Q264) In a given atom, no two electrons can have the same values for all the four quantum number. This is called
Show Answer

Q265) Electrons were discovered by
Show Answer

Q266) The conclusion that every additional electron enters the orbital with lowest possible energy has been drawn from
Show Answer

Q267) Neutron is denoted by Show Answer

Q268) Which of the following has more electrons than neutrons? Show Answer

Q269) The value of Planck's constant is Show Answer

Q270) Which experimental observation correctly accounts for the phenomenon? (read as Experimental observation : Phenomenon) Show Answer

Q271) Which of the following gave the idea of a nucleus of the atom? Show Answer

Q272) Which of the following expression imposes the condition of quantization of energy of an electron in an atom? Show Answer

Q273) According to Bohr's theory the angular momentum of an electron in the fourth orbit is Show Answer

Q274) The energy of an atom in the 3rd orbit is -E. The energy of an electron in the first orbit will be Show Answer

Q275) The value of Rydberg constant is Show Answer

Q276) Which of the following is false regarding Bohr's model? Show Answer

Q277) To which electron transition between Bohr orbitals in hydrogen does the second line in the Balmer series belong? Show Answer

Q278) The correct expression derived for the energy of an electron in the nth energy level of H-atom is Show Answer

Q279) Which of the following statement is incorrect? Show Answer

Q280) The unit of frequency of radiation is Show Answer

Q281) Which of the following is not correct? Show Answer

Q282) Mathematically, Heisenberg's uncertainty principle can best be explained by Show Answer

Q283) The number of electronic subshells in the nth quantum level are Show Answer

Q284) The number of orbitals in any shell (n) is equal to Show Answer

Q285) The maximum number of electrons present in any main energy level is given by Show Answer

Q286) The number of electrons in a sub shell is equal to Show Answer

Q287) Which of the following sets of quantum number is not permitted? Show Answer

Q288) Which d-orbital does not have four lobes? Show Answer

Q289) Which of the following statement is correct? Show Answer

Q290) Which of the following configuration is incorrect? Show Answer

Q291) The correct electronic configuration of nitrogen is Show Answer

Q292) Which one of the following shows the correct electronic configuration of the outermost shell in inert gas? Show Answer

Q293) In uni electron system, the wave number of a spectral line is directly proportional to Show Answer

Q294) Which of the following represents the de Broglie relation? Show Answer

Q295) Which of the following arrangements of electrons is most likely to be stable? Show Answer

Q296) Cathode rays have same charge to mass ratio as Show Answer

Q297) X-rays were discovered by: Show Answer

Q298) Two electrons in the same orbital may be identified with: Show Answer

Q299) An electron has principal quantum number 3. The number of its (i) subshells and (ii) orbitals would be respectively: Show Answer

Q300) Maximum number of electrons in a subshell of an atom is determined by the following: Show Answer

Q301) Particle having mass 200 times that of an electron is: Show Answer

Q302) Which of the following has the maximum number of unpaired electrons? Show Answer

Q303) An electron from one Bohr stationary orbit can go to next higher orbit Show Answer

Q304) How many neutrons are present in tritium nucleus? Show Answer

Q305) The statements, which is/are correct: Show Answer

Q306) Zeeman effect refers to the Show Answer

Q307) In potassium the order of energy level for 19th electron is: Show Answer

Q308) A strong argument for the particle nature of cathode rays is that they: Show Answer

Q309) What is the ration of mass of an electron to the mass of a proton? Show Answer

Q310) As the number of orbit increase from the nucleus, the difference between the adjacent energy levels: Show Answer

Q311) The orbital angular momentum of a p-electron is given as: Show Answer

Q312) Transition from n = 2, 3, 4, 5… to n = 1 is called Show Answer

Q313) If the total energy of an electron in a hydrogen like atom in an excited state is -3.4 eV, then the de Broglie wavelength of the electron is: Show Answer

Q314) Which d-orbital does not have four lobes? Show Answer

Q315) The nucleus of an atom contains Show Answer

Q316) Positive charge in an atom is: Show Answer

Q317) Total number of electrons present in acetylene molecule is: Show Answer

Q318) An ion which has 18 electrons in the outermost shell is: Show Answer

Q319) The maximum number of electrons in a p-orbital with n = 6 and m = 0 can be: Show Answer

Q320) Energy of photon of visible light is Show Answer

Q321) The photoelectric effect occurs only when the incident light has more frequency than a certain minimum: Show Answer

Q322) For which of the following, the radius will be same as for hydrogen atom having n = 1? Show Answer

Q323) The volume of a proton is approximately; Show Answer

Q324) Normally, the time taken in the transition is : Show Answer

Q325) When the value of azimuthal quantum number is 3, magnetic quantum number can have values: Show Answer

Q326) Positive rays or canal rays are: Show Answer

Q327) X-rays do not show the phenomenon of : Show Answer

Q328) Rydberg is : Show Answer

Q329) Which is not deflected by magnetic field: Show Answer

Q330) Increase in the frequency of the incident radiations increases the: Show Answer

Q331) One electron volt is: Show Answer

Q332) A quanta will have more energy, if : Show Answer

Q333) Which of the following electron transition in hydrogen atom will require largest amount of energy? Show Answer

Q334) The principal quantum number n can have integral values ranging from: Show Answer

Q335) The present atomic weight scale is: Show Answer

Q336) Which one of the following set of quantum numbers is not possible for electron in the ground state of an atom with atomic number 19? Show Answer

Q337) The total number of electrons present in all the 's' orbitals, all the 'p' orbitals and all the 'd' orbitals of cesium ion are respectively Show Answer

Q338) What is the lowest energy of the spectral line emitted by the hydrogen atom in the Lyman series? (h = Planck's constant, c = velocity of light, R = Rydberg's constant). Show Answer

Q339) The total number of electrons present in all the 's' orbitals, all the 'p' orbitals and all the 'd' orbitals of cesium ion are respectively, the velocity acquired by the electron will be; Show Answer

Q340) Which is not electromagnetic radiation? Show Answer

Q341) Magnetic quantum number for the last electron in sodium is: Show Answer

Q342) The Heisenberg's uncertainty principle can be applied to Show Answer

Q343) Which one of the following sets of quantum numbers represents the highest energy level in an atom? Show Answer

Q344) Isotopes are Show Answer

Q345) Which consists of particle of matter? Show Answer

Q346) Which element possess non-spherical shells? Show Answer

Q347) Splitting of spherical lines when atoms are subjected to strong electric field is called: Show Answer

Q348) The velocity of electron in first orbit of H-atoms as compared to the velocity of light is Show Answer

Q349) Which best describe the emission spectra of atomic hydrogen? Show Answer

Q350) In the ground state of the H-atom, the electron is : Show Answer

Q351) Which wave property is directly proportional to energy of electromagnetic radiation: Show Answer

Q352) Mass of an electron is : Show Answer

Q353) The number of electrons in a neutral atom of an element is equal to its: Show Answer

Q354) Which is the correct outermost shell configuration of chromium? Show Answer

Q355) Which of the following ion will show colour in aqueous solution? Show Answer

Q356) The highest number of unpaired electrons are in Show Answer

Q357) Maximum number of electrons in an orbit is given by: Show Answer

Q358) Compared to the mass of lightest nuclei, the mass of an electron is only (app.) Show Answer

Q359) The electronic configuration of the element which is just above the element with atomic number 43 in the same particle group is: Show Answer

Q360) The electric configuration of element with atomic number 24 is Show Answer

Q361) The order of filling of electrons in the orbital of an atom will be: Show Answer

Q362) Which one of the following pair of atoms/atom-ion have identical ground state configuration? Show Answer

Q363) A gas absorbs photon of 355 nm and emits at two wavelengths. If one of the emission is at 680 nm, the other is at Show Answer

Q364) Compared to mass of lightest nucleus the mass of an electron is only: Show Answer

Q365) Bohr's model violates the rules of classical physics because it assumes that: Show Answer

Q366) Which of the following statements does not form a part of Bohr's model of hydrogen atom? Show Answer

Q367) Bragg's equation will have no solution, if: Show Answer

Q368) Size of the nucleus is: Show Answer

Q369) Penetration power of proton is: Show Answer

Q370) Which of the following elements has least number of electrons in its M-shell? Show Answer

Q371) The mass of an electron is m, its charge e and it is accelerated from rest through a potential difference V. The kinetic energy of the electron in joules will be : Show Answer

Q372) In an atom wave mechanics suggests that electrons: Show Answer

Q373) Splitting of spectrum lines in magnetic field is Show Answer

Q374) Which of the following is non-permissible? Show Answer

Q375) Which electronic configuration does not follow the Pauli's exclusion principle? Show Answer

Q376) Which of the following atoms has same number of protons and neutrons in its nucleus? Show Answer

Q377) The ratio of the difference in energy between the first and the second Bohr orbit to that between the second and the third Bohr orbit is Show Answer

Q378) In an atom with atomic number 29, mass number 59, the number of electrons is: Show Answer

Q379) In which orbital electron is most tightly bound to the nucleus? Show Answer

Q380) Which of the following is correctly matched? Show Answer

Q381) Threshold wavelength depends upon: Show Answer

Q382) Which of the following is not possible? Show Answer

Q383) The atomic radius is of the order of : Show Answer

Q384) Light, a well known form of energy, is treated as a form of matter, by saying that it consist of : Show Answer

Q385) When the azimuthal quantum number has the value of 2, the number of orbitals possible are Show Answer

Q386) Compared to the lightest atom the heaviest atom weighs: Show Answer

Q387) In a hydrogen atom, if energy of an electron in ground state is -13.6 eV, then that in the 2nd excited state is: Show Answer

Q388) Which of the following sets of quantum number is correct for an electron in 4f-orbital? Show Answer

Q389) If the following particles travel with equal speed, then for which particle the wavelength will be longest? Show Answer

Q390) The orbital cylindrically symmetrical about x-axis is: Show Answer

Q391) The ratio of radii of two nuclei with mass numbers 27 and 64 is Show Answer

Q392) The orbital with maximum number of possible orientations is: Show Answer

Q393) The orbital closest to the nucleus is: Show Answer

Q394) Isoelectronic pair among the following is Show Answer

Q395) The number of valence electrons in completely excited sulphur atom is: Show Answer

Q396) The work-function for photoelectric effect : Show Answer

Q397) Line spectra is characteristic of : Show Answer

Q398) An improbable configuration is: Show Answer

Q399) The wave number of radiation of wavelength 500 nm is: Show Answer

Q400) Which of the following is the correct form of Schrodinger wave equation? Show Answer

Q401) If n = 6, the correct sequence for filling of electrons will be: Show Answer

Q402) Which one is not true for the cathode rays? Show Answer

Q403) Moseley's law is : (a and b are constants, Z = atomic number, v = frequency) Show Answer

Q404) From the discharge tube experiment, it is concluded that: Show Answer

Q405) Which atom has as many as s-electrons as p-electrons? Show Answer

Q406) Mosley's name is connected with the discovery of : Show Answer

Q407) For a Bohr atom angular momentum M of the electron is (n = 0, 1, 2, ...) Show Answer

Q408) When 3d-orbital is complete, the newly entering electron goes into: Show Answer

Q409) Which of the followings sets of quantum numbers represents the highest energy of an atom? Show Answer

Q410) When an electron jumps from L- level to M - level, there occurs: Show Answer

Q411) If the kinetic energy of an electron is increased four times, the wavelength of the de-Broglie wave associated with it would becomes Show Answer

Q412) The discovered of neutrons become very late because Show Answer

Q413) "Positronium" is the name given to an atom-like combination formed between: Show Answer

Q414) The nucleus of helium contains: Show Answer

Q415) Photoelectric effect shows: Show Answer

Q416) When high speed electrons strike a target: Show Answer

Q417) The de Broglie wavelength of a particle with mass 1 g and velocity 100 m/s is: Show Answer

Q418) Photoelectric effect can be caused by : Show Answer

Q419) Deflection back of a few particles on hitting thin foil of gold shows that Show Answer

Q420) An atom has 2 electrons in K-shell, 8 electrons in L-shell and 6 electrons in M-shell. The number of s-electrons present in the element is: Show Answer

Q421) The angular momentum of an electron in 2 p-orbital is : Show Answer

Q422) Which set has the same number of s-electrons? Show Answer

Q423) Which wavelength falls in a X-rays region? Show Answer

Q424) Of the following transitions in hydrogen atom, the one which gives an absorption line of lowest frequency is : Show Answer

Q425) Which is not in accordance to aufbau principle? Show Answer

Q426) Which of the following has more number of unpaired electron? Show Answer

Q427) The scientist who proposed the atomic model based on the quantization of energy for the first time is Show Answer

Q428) The energy of the electron in first Bohr's orbit is -13.6eV. The energy of the electron in its first excited state is Show Answer

Q429) Cathode rays are produced when the pressure in the discharge tube is of the order of : Show Answer

Q430) Number of electrons in nucleus of an element of atomic number 14 is: Show Answer

Q431) The study of photoelectric effect is useful in understanding: Show Answer

Q432) The ratio of radius of III and IV Bohr's orbits in hydrogen atom is: Show Answer

Q433) When an electron of charge e and mass m moves with velocity u about the nuclear charge Ze in the circular orbit of radius r, the potential energy of the electron is given by: Show Answer

Q434) Which diagram best represents the appearance of the line spectrum of atomic hydrogen in the visible region? Show Answer

Q435) If the electron of a hydrogen atom is present in the first orbit, the total energy of the electron is Show Answer

Q436) The number of elliptical orbits, including circular orbits in the M-shell of an atom is: Show Answer

Q437) Wave mechanical model of the atom depends upon: Show Answer

Q438) The orbital angular momentum of an electron revolving in a p-otbital is Show Answer

Q439) The velocity of a photon is: Show Answer

Q440) Possible values of 'm' for a given value of n are: Show Answer

Q441) Common name for proton and neutron is Show Answer

Q442) A node is a surface on which the probability of finding an electron is: Show Answer

Q443) In photoelectric effect, the photo-current: Show Answer

Q444) Possible number of orientations of a subshell is: Show Answer

Q445) The orientation of an atomic orbital is governed by: Show Answer

Q446) The ratio of the radius of the orbit for the electron orbiting the hydrogen nucleus to that of an electron orbiting a deuterium nucleus is: Show Answer

Q447) Which of the following sets of quantum numbers is correct for an electron in 4f-orbital? Show Answer

Q448) The electronic energy levels of the hydrogen atom in the Bohr's theory are called: Show Answer

Q449) A photoelectric cell is a device, which : Show Answer

Q450) An f-shell containing 6 unpaired electrons can exchange Show Answer

Q451) Radius of nucleus is proportional to …where A is mass number Show Answer

Q452) Which possesses an inert gas configuration? Show Answer

Q453) Choose the correct statement among the following Show Answer

Q454) In ground state of chromium atom (Z = 24) the total number of orbitals populated by one or more electrons is: Show Answer

Q455) The observation that the ground state of nitrogen atom has 3 unpaired electrons in its electronic configuration and not otherwise is associated with Show Answer

Q456) Which set is not correct? Show Answer

Q457) The mass of a neutron is of the order of: Show Answer

Q458) As an electron is brought from an infinite distance close to the nucleus of the atom, the energy of the electron-nucleus system: Show Answer

Q459) Beryllium's fourth electron will have the four quantum numbers: Show Answer

Q460) The electrons would go to lower energy levels first and then to higher energy levels according to which of the following? Show Answer

Q461) Which among the following species have the same number of electrons in its outermost as well as penultimate shell? Show Answer

Q462) Photons of energy 6 eV are incidented on a potassium surface of work function 2.1 eV. What is the stopping potential? Show Answer

Q463) When the speed of electron increase, the specific charge: Show Answer

Q464) If uncertainty in position and momentum are equal, then uncertainty in velocity is: Show Answer

Q465) Two electron in an atm of an element cannot have: Show Answer

Q466) The energy of electromagnetic radiation depends on: Show Answer

Q467) Which type of radiation is not emitted by the electronic structure of atoms? Show Answer

Q468) The difference between ions and atoms is of: Show Answer

Q469) The statements are valid for :
(i) In filling a group of orbitals of equal energy, it is energetically preferable to assign electrons to empty orbitals rather than pair them into a particular orbital
(ii) When two electrons are placed in two different orbitals, energy is lower if the spins are parallel Show Answer

Q470) In the absence of magnetic field p-orbitals are known as… fold degenerate Show Answer

Q471) In hydrogen spectrum least energetic transition of electrons are found in: Show Answer

Q472) The ground state term symbol for an electronic state is governed by Show Answer

Q473) In hydrogen atom, which energy level order is not correct: Show Answer

Q474) One energy difference between the states n=2 and n=3 is E eV, in hydrogen atom. The ionisation potential of H atom is: Show Answer

Q475) The atomic number of an element is 17. The number of orbitals containing electron pairs in the valency shell is: Show Answer

Q476) Which statement is relating to the spectrum of H atom is false ? Show Answer

Q477) The de Broglie wavelength associated with a material particle is: Show Answer

Q478) Naturally occurring elements are mixtures of: Show Answer

Q479) 1 fermi is equal to : Show Answer

Q480) When an electron moves from higher orbit to a lower orbit … is produced Show Answer

Q481) The Atomic number of the element having maximum number unpaired 3p - electrons is Show Answer

Q482) A photon in X region is more energetic than in the visible region X is: Show Answer

Q483) The stability of ferric ion is due to Show Answer

Q484) According to aufbau principle, the correct order of energy of 3d, 4s and 4p-orbitals is Show Answer

Q485) The maximum wavelength of light that can excite an electron from first to third of hydrogen atom is Show Answer

Q486) The H-spectrum show Show Answer

Q487) The total number of protons present in all the elements upto 'Zn' in the periodic table is: Show Answer

Q488) Orbitals processing the same energy are called: Show Answer

Q489) Which set has the same number of unpaired electrons in their ground state? Show Answer

Q490) The atomic number of an element is 35 and its mass is 81. The number of electrons in its outermost shell is Show Answer

Q491) According to Dalton's atomic theory, the smallest particle which is capable of independent existence is: Show Answer

Q492) The possibility of finding an electron in an orbital was conceived by: Show Answer

Q493) Which statement is/are correct? Show Answer

Q494) The incorrect statement about bohr's orbit of hydrogen is atom is Show Answer

Q495) When electrons in N-shell of excited hydrogen atom return to ground state, the number of possible line spectrum is Show Answer

Q496) The electrons occupying the same orbital have always spin. Show Answer

Q497) The energy of hydrogen atom in its ground -13.6 eV. The energy of the level corresponding to the quantum number n = 5 is Show Answer

Q498) According to Bohr's theory, the angular momentum for an electron of 5th orbit is Show Answer

Q499) Correct set of four quantum number for valance electron of rubidium (Z = 37) is Show Answer

Q500) The total number of orbitals possible for principal quantum number n is Show Answer

Q501) which does not characterise X-rays? Show Answer

Q502) The velocity of an electron placed in third orbit of H atom, will be Show Answer

Q503) The orbital angular momentum of an electron in 2s orbital is Show Answer

Q504) In the atomic spectrum of hydrogen the series lines observed in the visible region is Show Answer

Q505) According to Bohr's model of hydrogen atom Show Answer

Q506) Which transition of electron in the hydrogen atom emits maximum energy? Show Answer

Q507) The quantum number that does not describe the distance and the angular disposition of the electron Show Answer

Q508) In H-atom ,the electron is de-excited from 5th shell to 1st shell. How many different lines may appear in line spectrum? Show Answer

Q509) The electronic configuration with maximum energy will be Show Answer

Q510) The orbital diagram in which aufbau principle is violated is Show Answer

Q511) The number of spherical nodes in 3p orbital is Show Answer

Q512) Ultraviolet light of 6.2 eV falls on aluminium surface (work function = 4.2 eV). The kinetic energy (in joule) of the fastest electron emitted is approximately. Show Answer

Q513) The value of quantum numbers for the outermost electron in scandium (Sc = 21) are; Show Answer

Q514) Each p-orbital and d-orbital except one has lobes respectively as: Show Answer

Q515) The wavelength of radiations emitted when H in atom,electrons fall from electron to stationary state 1 is: Show Answer

Q516) Select the odd man Show Answer

Q517) Assuming the velocity be same, which sub-atomic particle possesses smallest de Broglie wavelength; Show Answer

Q518) The chromium has different electronic configuration then what is expected according to aufbau principle because Show Answer

Q519) If the ionisation potential for hydrogen atom is 13.6eV, then the wavelength of light required for the ionisation of hydrogen atom would be: Show Answer

Q520) Bohr's atomic theory gave the idea of Show Answer

Q521) Which species has more electrons than protons? Show Answer

Q522) Electronic configuration of niobium (Nb = 41) is: Show Answer

Q523) X-rays cannot penetrate through a sheet of: Show Answer

Q524) How many electrons can fit into the orbitals that comprise the 3rd quantum shell? Show Answer

Q525) The total values of magnetic quantum number of an electron when the value of n = 2 is: Show Answer

Q526) The binding energy of the electron in the lowest orbit of the hydrogen atom is 13.6 eV. The energies required in eV to remove an electron from three lowest orbits of the hydrogen atom are: Show Answer

Q527) The best metal to be used for photoemission is: Show Answer

Q528) The probability of finding the electron in the orbital is Show Answer

Q529) The correct de Broglie relationship is: Show Answer

Q530) Electronic configuration of tritium is : Show Answer

Q531) The correct set of quantum numbers (n,l and m respectively) for the unpaired electron of chlorine atom is Show Answer

Q532) Total number of unpaired electrons, in an unexcited atom of atomic number 29 is: Show Answer

Q533) The work function for a metal is 4 eV. To emit a photoelectron of zero velocity from the surface of the metal, the wavelength of incident light should be: Show Answer

Q534) The wave number of the first line in the Lyman series in hydrogen spectrum is Show Answer

Q535) The nodes present in 3p-orbitals are Show Answer

Q536) Electronic configuration of deuterium atom is Show Answer

Q537) Which of the following sets of quantum numbers is correct? Show Answer

Q538) Which hydrogen like species will have same radius as that of Bohr orbit hydrogen atom? Show Answer

Q539) The expression Ze gives : Show Answer

Q540) Which has the highest number of unpaired electrons? Show Answer

Q541) The ratio between the neutrons present in carbon and silicon with respect to atomic masses of 12 and 28 is: Show Answer

Q542) The last electron placed in the third (n = 3) quantum shell for: Show Answer

Q543) The number of spectral lines that can be possible when electrons in 7th shell in different hydrogen atoms return to the 2nd shell, is Show Answer

Q544) The value of Rydberg constant is Show Answer

Q545) In absence of Pauli exclusion principle, the electronic configuration of Li in ground state may be: Show Answer

Q546) Which relates to light only as stream of particles? Show Answer

Q547) Who introduced the concept of electron spin? Show Answer

Q548) The unit of wavelength (nm) is equal to: Show Answer

Q549) Mass of neutron is … times the mass of electron Show Answer

Q550) The highest excited state that unexcited hydrogen atom can reach when they are bombarded with 12.2 eV electron is : Show Answer

Q551) The total number of atomic orbitals in fourth energy level of an atom is: Show Answer

Q552) The orbital angular momentum of an electron in a d-orbital is Show Answer

Q553) The space between the proton and electron in hydrogen atom is: Show Answer

Q554) Particles, which can be added to the nucleus of an atom without changing the chemical properties, are called: Show Answer

Q555) When 4f-level of an atom is completely filled with electrons, the next electron will enter: Show Answer

Q556) The total number of electrons that can be accommodated in all the orbitals having principal quantum number 2 and azimuthal quantum number 1 is: Show Answer

Q557) Suppose a completely filled or half filled set of p or d-orbitals is spherically symmetrical. Point out the species, which is spherical symmetrical? Show Answer

Q558) The number of electrons and neutrons of an element is 18 and 20 respectively. Its mass number is Show Answer

Q559) Which d-orbital has different shape from rest of all d-orbital? Show Answer

Q560) Photoelectric effect is the phenomenon in which: Show Answer

Q561) When the value of azimuthal quantum number is 1, magnetic quantum number can have values: Show Answer

Q562) The H atom electron dropped from n = 3 to n = 2, then energy emitted is Show Answer

Q563) The maximum number of sublevels, orbitals and electrons in N-shell of an atom are respectively Show Answer

Q564) Millikan's oil drop experiment is used to find: Show Answer

Q565) The maximum number of unpaired electrons present in 4f-energy level is: Show Answer

Q566) The target used for production of X-ray beam must have: Show Answer

Q567) According to Bohr's model of the hydrogen atom, the radius of a stationary orbit characterised by the principle quantum number n is proportional to: Show Answer

Q568) Which one of the following has unit positive charge and 1 u mass? Show Answer

Q569) Among the following sets of quantum numbers, which one is incorrect for 4d-electron? Show Answer

Q570) An electrons is in one of the 3d-orbitals, which of the quantum number is not possible? Show Answer

Q571) The momentum of a photon is p. The corresponding wavelength is: Show Answer

Q572) Which one of the following sets of ions represents a collection of isoelectronic species? Show Answer

Q573) An electron, a proton and an alpha particle have KE of 16E, 4E and E respectively. What is the qualitative order of their de-Broglie wavelengths? Show Answer

Q574) The e/m ratio is maximum for: Show Answer

Q575) The principle, which gives a way to fill the electrons in the available energy level is: Show Answer

Q576) Which of the following has the maximum number of unpaired 'd' electrons? Show Answer

Q577) Out of first 100 elements, number of elements having electrons in 3d-orbitals are: Show Answer

Q578) Identify the least stable ion amongst the following Show Answer

Q579) Mass number of atom represents the number of its: Show Answer

Q580) Number of electrons in the outermost orbit of the element of atomic number 15 is: Show Answer

Q581) Ionisation potential of hydrogen atom is 13.6 eV. Hydrogen atom in the ground state are excited by monochromatic light of energy 12.1 eV. The spectral lines emitted by hydrogen according to Bohr's theory will be: Show Answer

Q582) The line spectrum observed when electron falls from the higher level into L-level is known as: Show Answer

Q583) The angular momentum of electron of H-atom is proportional to: Show Answer

Q584) Which set of quantum number represents the electron of the lowest energy? Show Answer

Q585) Electron behaves both as a particle and a wave. This was proposed by Show Answer

Q586) The number of waves in an orbit are Show Answer

Q587) Which is not basic postulate of Dalton's atomic theory? Show Answer

Q588) p-orbitals of an atom in presence of magnetic field are: Show Answer

Q589) The valency orbital configuration of an element with Z = 23 is: Show Answer

Q590) In 'aufbau principle', the term aufbau represents: Show Answer

Q591) A particle of mass, 'm' when annihilated completely given an energy E equal to: Show Answer

Q592) The correct set of four quantum number for the valence electron of rubidium (Z=37) is Show Answer

Q593) An atom has net charge of -1. It has 18 electrons and 20 neutrons. Its mass number is: Show Answer

Q594) A photon is: Show Answer

Q595) Which orbital is dumb-bell shaped? Show Answer

Q596) Which of the following is related with both wave nature and particle nature? Show Answer

Q597) Aufbau principle does not give the correct arrangement of filling up of atomic orbital's in Show Answer

Q598) Ordinary oxygen contains: Show Answer

Q599) The approximate quantum number of a circular orbit of diameter, 20.6 nm of the hydrogen atom according to Bohr's theory is: Show Answer

Q600) A p-orbital in a given shell can accommodate upto Show Answer

Q601) An electron beam is accelerated through a potential difference of 10,000 volt. The de-Broglie wavelength of the electron beam is Show Answer

Q602) Transition of electron from n = 3 to n = 1 level results in: Show Answer

Q603) A cricket ball of 0.5 kg is moving with a velocity of 100 m/s. The wavelength associated with its motion is Show Answer

Q604) The ratio of the masses of proton and neutron are: Show Answer

Q605) The ratio between kinetic energy and the total energy of the electrons of hydrogen atom according to Bohr's model is: Show Answer

Q606) If the mass number of an element is W and its atomic number is N, then: Show Answer

Q607) Binding energy of hydrogen atom is 13.6 eV. The binding energy of a singly ionised helium atom is: Show Answer

Q608) Neutron was discovered by: Show Answer

Q609) For a particular value of azimuthal quantum number, the total number of magnetic quantum number values are given by Show Answer

Q610) The relation between energy of a radiation and its frequency was given by: Show Answer

Q611) The filling of 4p-sublevel starts in the element of atomic number: Show Answer

Q612) The angular speed of the electron in the nth orbit of Bohr hydrogen atom is: Show Answer

Q613) The chlorine atom differs from chloride ion in the number of: Show Answer

Q614) Which orbital does not possess angular node? Show Answer

Q615) The azimuthal quantum number for an electron in a 5d-orbital is: Show Answer

Q616) According to Bohr's theory, the angular momentum for an electron of 3rd orbit is Show Answer

Q617) Nuclides: Show Answer

Q618) The de-Broglie equation applies Show Answer

Q619) Which of the following electronic configuration is not possible? Show Answer

Q620) The maximum energy is possessed by an electron, when it is present Show Answer

Q621) Maximum number of electrons which can be accommodated in a g-subshell is: Show Answer

Q622) The radii of two of the first four Bohr's orbits of the hydrogen atom are in the ratio 1∶4. The energy difference between them may be: Show Answer

Q623) The compound in which cation is isoelectronic with anion is Show Answer

Q624) If each hydrogen atom is excited by giving 8.4 eV of energy, then the number of spectral lines emitted is equal to: Show Answer

Q625) The electronic configuration of silver atom in ground state is: Show Answer

Q626) Which is correct in case of p-orbitals? Show Answer

Q627) X-rays and γ-rays of same energies may be distinguished by: Show Answer

Q628) A neutral atom always consist of : Show Answer

Q629) The first emission line of Balmer series for H-spectrum has the wave no. equal to: Show Answer

Q630) A photon of 300 nm is absorbed by a gas then re-emits two photons. One re-emitted photon has wavelength 496 nm, the wavelength of second re-emitted photon is: Show Answer

Q631) Which statement does not form part of Bohr's model of the hydrogen atom? Show Answer

Q632) If uncertainties in the measurement of position and momentum of an electron are equal, the uncertainty in the measurement of velocity is Show Answer

Q633) Which of the following is correct for number of electrons, number of orbitals respectively in n-orbit? Show Answer

Q634) The quantum number sufficient to describe the electron in H atom is: Show Answer

Q635) If an isotope of hydrogen has two neutrons in its atom, its atomic number and mass number will be: Show Answer

Q636) The speed of the cathode rays is: Show Answer

Q637) Bohr model can explain Show Answer

Q638) Which of the following statement is relation to the hydrogen atom is correct? Show Answer

Q639) The nature of canal rays depends on: Show Answer

Q640) Neutron possesses: Show Answer

Q641) Cathode-ray tube is used in: Show Answer

Q642) Non-directional orbital is Show Answer

Q643) The maximum sum of the number of neutrons and proton is an isotope of hydrogen is : Show Answer

Q644) The principal quantum number of an atom represents: Show Answer

Q645) The specific charge for positive rays is much less than the specific charge for cathode rays. This is because: Show Answer

Q646) The magnetic moment of electron in an atom (excluding orbital magnetic moment) is given by: Show Answer

Q647) de Broglie equation is a relationship between: Show Answer

Q648) Which electromagnetic radiation has extremely small wavelength? Show Answer

Q649) The maximum number of 3d-electrons having spin quantum number s = +1/2 are: Show Answer

Q650) Dimensions of Planck's constant are: Show Answer

Q651) If helium atom and hydrogen molecules are moving with the same velocity, their wavelength ratio will be Show Answer

Q652) All types of electromagnetic radiations possess same: Show Answer

Q653) Which is not permissible subshell? Show Answer

Q654) In Bohr's series of lines of hydrogen spectrum, the third line from the red end corresponds to which one of the following inner-orbit jumps of the electron for Bohr orbit in an atom of hydrogen? Show Answer

Q655) Which represents the correct set up of the four quantum numbers of 4s-electron? Show Answer

Q656) Ground state electronic configuration of nitrogen atom can be represented as Show Answer

Q657) Electron in the atom are held by: Show Answer

Q658) If the electron in the hydrogen atom is excited to n=5, the number of different frequencies of radiations which may be emitted is: Show Answer

Q659) The uncertainty principle and the concept of wave nature of matter was proposed by … and … respectively Show Answer

Q660) According to Bohr's theory, the angular momentum of an electron in 5th orbit is Show Answer

Q661) Positron is: Show Answer

Q662) Quantum theory was postulated by: Show Answer

Q663) Which of the following expressions gives the de-Broglie relationship? Show Answer

Q664) Three electrons in p-sublevel must have the quantum number: Show Answer

Q665) The number of vacant d-orbitals in completely excited Cl atom is: Show Answer

Q666) The mass number of an element is 23 and atomic number is 11. The number of protons, electrons and neutrons respectively present in the atom of the elements are: Show Answer

Q667) The planck's constant has a unit of: Show Answer

Q668) The quantum numbers of most energetic electron in Ne atom when it is in first excited state is: Show Answer

Q669) The number of p-electrons in bromine atom is Show Answer

Q670) Potassium ion is isoelectronic with the atom of: Show Answer

Q671) Density of the electron is: Show Answer

Q672) Cr has electronic configuration as Show Answer

Q673) The number of electrons accommodated in an orbit with principle quantum number 2, is Show Answer

Q674) The number of vacant orbitals of element with atomic number 14 is: Show Answer

Q675) Which of the following is correct? Show Answer

Q676) Energy of H-atom in the ground state is -13.6 eV, hence energy in the second excited state is Show Answer

Q677) Nuclear theory of the atom was put forward by Show Answer

Q678) Which of the following is not permissible arrangement of electrons in an atom? Show Answer

Q679) An atom having even number of electrons may be: Show Answer

Q680) Dual nature of particles was proposed by Show Answer

Q681) In photoelectric effect, the number of photoelectrons emitted is proportions to Show Answer

Q682) The number of radial nodes of 3s and 2p-orbitals are respectively Show Answer

Q683) Correct set of four quantum numbers of a 4d-electron is: Show Answer

Q684) The orbital angular momentum of an electron in 3s-orbital is Show Answer

Q685) Atoms in hydrogen gas have preponderance of: Show Answer

Q686) The energy of the electron at infinite distance from the nucleus in Bohr's model is taken a: Show Answer

Q687) The maximum number of electrons possible in a sublevel is equal to: Show Answer

Q688) The radius of second stationary orbit in Bohr's atoms is R. The radius of third orbit will be: Show Answer

Q689) In photoelectric emission the energy of the emitted electrons is: Show Answer

Q690) The triad of nuclei which is isotonic is Show Answer

Q691) Angular momentum of an electron in an orbital is given by : Show Answer

Q692) The charge on an electron was discovered by Show Answer

Q693) In hydrogen spectrum most energetic transitions of electrons are found in: Show Answer

Q694) Which property of elements is not a whole number? Show Answer

Q695) Proton is : Show Answer

Q696) Which of the following is Heisenberg uncertainty principle? Show Answer

Q697) Which of the following make up an isotonic triad? Show Answer

Q698) Which principle/rule limits the maximum number of electrons in an orbital to two? Show Answer

Q699) Magnitude of kinetic energy in an orbit is equal to Show Answer

Q700) The maximum number of atomic orbitals associated with a principal quantum number 5 is: Show Answer

Q701) The magnetic quantum number for valency electron of sodium is: Show Answer

Q702) Which pair has elements containing same number of electrons in the outermost orbit? Show Answer

Q703) The electromagnetic radiation with maximum wavelength is: Show Answer

Q704) An element contains: Show Answer

Q705) Heaviest particle is: Show Answer

Q706) The set of quantum numbers for the outermost electron for copper in its ground state is Show Answer

Q707) Atom containing an odd number of electron is: Show Answer

Q708) Amplification of electromagnetic waves by simulated emission of radiation produces: Show Answer

Q709) In the discharge tube emission of cathode rays requires: Show Answer

Q710) Which electron transition in a hydrogen atom requires the largest amount of energy? Show Answer

Q711) The angular momentum of an electron in an atomic orbital is governed by the: Show Answer

Q712) In Bohr's model of the hydrogen atom the ratio between the period of revolution of an electron in the orbit n = 1 to the period of revolution of the electron in the orbit n = 2 is: Show Answer

Q713) Different lines in Lyman series of hydrogen spectrum lie in …. region Show Answer

Q714) The atoms in a molecule vibrate around their mean position by stretching or bending out of place. These vibration and the energy they carry are studied by: Show Answer

Q715) Maximum number of electrons present in "N" shell is: Show Answer

Q716) Which electronic level will allow the hydrogen atom to absorb photon but not to emit? Show Answer

Q717) The mass of electron moving with velocity of light is: Show Answer

Q718) Which of the following particles moving with same velocity would be associated with smaller de-Broglie wavelength? Show Answer

Q719) The electron configuration of the oxide ion is much most similar to the electron configuration of the Show Answer

Q720) Stark effect refers to the Show Answer

Q721) For which species, Bohr's theory does not apply: Show Answer

Q722) Which of the subshell has double dumb-bell shape? Show Answer

Q723) The lightest particle is Show Answer

Q724) The radius of second Bohr's orbit of hydrogen atom is Show Answer

Q725) Which set of phenomenon shown by the radiation proves the dual nature of radiation? Show Answer

Q726) The hydrogen spectrum from an incandescent source of hydrogen is: Show Answer

Q727) The path of deflection of electron beam is: Show Answer

Q728) Which particle may be removed from a stable neutral atom with least energy change? Show Answer

Q729) Visible spectrum of hydrogen shows that it exists in two different forms which are based on direction of spin of the: Show Answer

Q730) Evidence for the existence of different energy levels in atom is supplied by: Show Answer

Q731) Which are in the ascending order of wavelength? Show Answer

Q732) The mass of one mole of electron is: Show Answer

Q733) According to Bohr's postulates which quantity can take up only discrete values: Show Answer

Q734) Which of the following reaction led to the discovery of neutrons? Show Answer

Q735) The radius of which of the following orbit is same as that of the first Bohr's orbit of hydrogen atom? Show Answer

Q736) Which has minimum number of unpaired d-electrons? Show Answer

Q737) The total spin for atoms with atomic number 7, 24, 34 and 36 will be Show Answer

Q738) A photo-sensitive metal is not emitting photo-electrons when irradiated. It will do so when threshold is crossed. To cross the threshold we need to increase : Show Answer

Q739) Which neutral atom has 18 electrons in its outer shell? Show Answer

Q740) Rutherford scattering formula fails for very small scattering angles because Show Answer

Q741) 3 p-orbital has: Show Answer

Q742) Rutherford's alpha particle scattering experiment eventually led to the conclusion that: Show Answer

Q743) The d-orbital with the orientation along X and Y axes is called: Show Answer

Q744) Which of the following transitions are not allowed in the normal electronic emission spectrum of an atom? Show Answer

Q745) In an atom two electrons move around the nucleus in circular orbits of radii R and 4R. The ratio of the time taken by them to complete one revolution is: Show Answer

Q746) The number of electrons and protons in an atoms of third alkaline earth metal is Show Answer

Q747) In photoelectric effect the number of photo-electron emitted is proportional to : Show Answer

Q748) Which of the following statements is wrong about cathode rays? Show Answer

Q749) In an atom no two electrons can have the same value for all the quantum numbers. This was proposed by: Show Answer

Q750) The minimum energy required to eject an electron from an atom is called: Show Answer

Q751) As electron moves away from the nucleus, its KE: Show Answer

Q752) A hydrogen atom in its ground state absorbs a photon. The maximum energy of such a photon is: Show Answer

Q753) Wave nature of electrons was demonstrated by Show Answer

Q754) The principal quantum number of H-atom orbital, if the electron energy is -3.4 eV, will be Show Answer

Q755) No two electrons can have the same values of …. quantum numbers. Show Answer

Q756) The first atom with incomplete d-shell is: Show Answer

Q757) Particle nature of electron was experimentally demonstrated by Show Answer

Q758) The difference in angular momentum associated with the electron in two successive orbits of hydrogen atom is: Show Answer

Q759) The volume of nucleus is about: Show Answer

Q760) The species having more electrons than neutrons is: Show Answer

Q761) Which ion has the maximum magnetic moment? Show Answer

Q762) Photoelectric effect was discovered by : Show Answer

Q763) When light is directed at the metal surface, the emitted electrons: Show Answer

Q764) The minimum real charge on of any particle, which can exist is: Show Answer

Q765) An electron jumps from an outer orbit to an inner orbit with an energy difference of 3.0eV. What will be the wavelength of the line emitted? Show Answer

Q766) Statement 1 : The charge to mass ratio of the particles in anode rays depends on nature of the gas taken in the discharge tube.
Statement 2 : The particles in anode rays carry positive charge. Show Answer

Q767) Statement 1 : Only principal quantum number determines the energy of an electron in an orbital in sodium atom.
Statement 2 : For one electron system, the expression of energy is the same as that obtained in Bohr's theory. Show Answer

Q768) Statement 1 : Kinetic energy of photoelectrons is directly proportional to the intensity of the incident radiation.
Statement 2 : Each photon of light causes the emission of only one photoelectrons. Show Answer

Q769) Statement 1 : Radiant energy of quantum is given by E = h v.
Statement 2 : Quantum in the energy equation signifies the principal quantum number. Show Answer

Q770) Hydrogen has three isotopes (A), (B) and (C). If the number of neutron(s) in (A), (B) and (C) respectively, are (x), (y) and (z), the sum of (x), (y) and (z) is Show Answer

Q771) Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying 0.5 V when the radiation of 250 nm is used. The work function of the metal is Show Answer

Q772) Given below are two statements, one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) In the photoelectric effect, the electrons are ejected from the metal surface as soon as the beam of light of frequency greater than threshold frequency strikes the surface.
Reason (R) When the photon of any energy strikes an electron in the atom, transfer of energy from the photon to the electron takes place.
In the light of the above statements, choose the most appropriate answer from the options given below. Show Answer

Q773) If the Thomson model of the atom was correct, the result of Rutherford's gold foil experiment would have been Show Answer

Q774) Which of the graphs shown below does not represent the relationship between incident light and the electron ejected from metal surface? Show Answer

Q775) The number of incorrect statement/s about the black body from the following is . . . . . . .
(A) Emit or absorb energy in the form of electromagnetic radiation.
(B) Frequency distribution of the emitted radiation depends on temperature.
(C) At a given temperature, intensity vs frequency curve the passes through a maximum value.
(D) The maximum of the intensity vs frequency curve is at a higher frequency at higher temperature compared to that at lower temperature. Show Answer

Q776) When the wavelength of radiation falling on a metal is changed from 500 nm to 200 nm, the maximum kinetic energy of the photoelectrons becomes three times larger. The work function of the metal is Show Answer

Q777) In a photoelectric effect experiment the threshold wavelength of light is 380 nm. If the wavelength of incident light is 260 nm, the maximum kinetic energy of emitted electrons will be approximately Show Answer

Q778) Given below are two statements.
Statement I According to Bohr's model of hydrogen atom, the angular momentum of an electron in a stationary state is quantised.
Statement II The concept of electron in Bohr's orbit, violates the Heisenberg uncertainty principle.
In the light of the above statements, choose the most appropriate answer from the options given below. Show Answer

Q779) Given below are two statements
Statement I Rutherford's gold foil experiment cannot explain the line spectrum of hydrogen atom.
Statement II Bohr's model of hydrogen atom contradicts Heisenberg's uncertainty principle.
In the light of the above statements, choose the most appropriate answer from the options given below: Show Answer

Q780) The region in the electromagnetic spectrum where the Balmer series lines appear is Show Answer

Q781) The ratio of the shortest wavelength of two spectral series of hydrogen spectrum is found to be about 9. The spectral series are Show Answer

Q782) If m and e are the mass and charge of the revolving electron in the orbit of radius r for hydrogen atom, the total energy of the revolving electron will be Show Answer

Q783) According to Bohr's theory, the angular momentum of an electron in 5th orbit is Show Answer

Q784) Given below are two statements.
Statement I According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in positive charges on the nucleus as there is no strong hold on the electron by the nucleus.
Statement II According to Bohr's model of an atom, qualitatively the magnitude of velocity of electron increases with decrease in principal quantum number.
In the light of the above statements, choose the most appropriate answer from the options given below. Show Answer

Q785) Which of the following statements is false? Show Answer

Q786) Which of the following is the energy of a possible excited state of hydrogen? Show Answer

Q787) The number of following statement/s which is/are incorrect is
(1) line emission spectra are used to study the electronic structure.
(2) the emission spectra of atoms in the gas phase show a continuous spread of wavelength from red to violet.
(3) an absorption spectrum is like the photographic negative of an emission spectrum.
(4) the element helium was discovered in the sun by spectroscopic method. Show Answer

Q788) If wavelength of the first line of the Paschen series of hydrogen atom is 720 nm, then the wavelength of the second line of this series is . . . . . . . . nm. (Nearest integer) Show Answer

Q789) When the excited electron of a H-atom from n = 5 drops to the ground state, the maximum number of emission lines observed are . . . . . . . Show Answer

Q790) Given below are two statements
Statement I According to Bohr atomic model, electron revolve in an orbit without loss of energy. Statement II Stationary orbit has equal value of centrifugal and electrostatic force.
In the light of the above statements, choose the most appropriate answer form the options given below. Show Answer

Q791) The energy of an electron in the first Bohr orbit for hydrogen is -13.6 eV. Which one of the following is a possible excited state for electron in Bohr orbit of hydrogen atom? Show Answer

Q792) The limiting line in Balmer series will have a frequency of Show Answer

Q793) The de-Broglie wavelength of an electron in the 4 Bohr orbit is Show Answer

Q794) The de-Broglie's wavelength of electron present in first Bohr orbit of 'H' atom is Show Answer

Q795) An electron in a hydrogen atom in its ground state absorbs 2 times as much energy as the minimum required to for it to escape from the atom. What is the wavelength of the emitted electron? Show Answer

Q796) The number of radial nodes for 3 p-orbital is Show Answer

Q797) The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is Show Answer

Q798) Identify the incorrect statement from the following. Show Answer

Q799) Which of the following sets of quantum numbers is not allowed? Show Answer

Q800) Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A) Energy of 2s orbital of hydrogen atom is greater than that of 2s orbital of lithium.
Reason (R) Energies of the orbitals in the same subshell decrease with increase in the atomic number. In the light of the above statements, choose the correct answer from the options given below: Show Answer

Q801) The number of radial and angular nodes in 4d orbital are respectively Show Answer

Q802) The total number of orbitals associated with the principal quantum number 5 is Show Answer

Q803) Which of the following sets of quantum numbers is correct for an electron in 4 f-orbital? Show Answer

Q804) The four quantum numbers for the electron in the outermost orbital of potassium (atomic no. 19) are Show Answer

Q805) Given below are two statements.
Statement I The orbitals having same energy are called as degenerate orbitals.
Statement II In hydrogen atom, 3 p and 3 d orbitals are not degenerate orbitals.
In the light of the above statements, choose the most appropriate answer from the options given below Show Answer

Q806) A certain orbital has no angular nodes and two radial nodes. The orbital is Show Answer

Q807) The orbital having two radial as well as two angular Show Answer

Q808) Consider the hypothetical situation where the azimuthal quantum number, l takes values 0, 1, 2, . . . . n + 1, where n is the principle quantum number. Then, the element with atomic number Show Answer

Q809) The correct statement about probability density (except at infinite distance from nucleus) is Show Answer

Q810) Among the following, the energy of 2s-orbital is lowest in Show Answer

Q811) If the principal quantum number n = 6, the correct sequence of filling of electrons will be Show Answer

Q812) Which of the following sets of quantum numbers represent the highest energy of an atom? Show Answer

Q813) The figure that is not a direct manifestation of the quantum nature of atoms is Show Answer

Q814) The number of correct statements from the following is
A. For 1 s orbital, the probability density is maximum the nucleus.
B. For 2 s orbital, the probability density first increases to maximum and then decreases sharply to zero.
C. Boundary surface diagrams of the orbitals enclose a region of 100% probability of finding the electron.
D. p and d-orbitals have 1 and 2 angular nodes respectively.
E. Probability density of p-orbital is zero at the nucleus. Show Answer

Q815) The number of atomic orbitals from the following having 5 radial nodes is . . . . . . .7s, 7p, 6s, 8p, 8d Show Answer

Q816) Given the set of four quantum number that could represent the last electron added (using the Aufbau principle) to the Sr atom. Show Answer