Practice Test

Q1) The temperature and pressure at which all the three phases of a substance coexist is called the Show Answer

Q2) The SI unit of thermal conductivity (K) is Show Answer

Q3) The triple point of carbon dioxide is 216.55 K . This temperature on the Fahrenheit scale is Show Answer

Q4) A meter long narrow bore held horizontally (and closed at one end) contains a 76 cm long mercury thread which traps a 15 cm column of air. When the tube is held vertically with the open end at the bottom, the length of mercury that flows out is Show Answer

Q5) Estimate the ratio of their number of molecules. Show Answer

Q6) Estimate the mass densities of Neon to Oxygen in vessel. Show Answer

Q7) Obtain the ratio of average kinetic energy per molecule of argon to chlorine. Show Answer

Q8) By what percentage should the pressure of a given mass of a gas be increased so as to decrease its volume by 10% at a constant temperature? Show Answer

Q9) The equation PV = n R T can safely describe the behavior of a real gas at Show Answer

Q10) Boyle's law is applicable in Show Answer

Q11) The order of magnitude of the number of nitrogen molecules in an air bubble of diameter 2 mm under ordinary conditions is Show Answer

Q12) At a constant pressure, of the following graphs the one which represents the variation of the density of an ideal gas with the absolute temperature T, is Show Answer

Q13) A vessel if filled with a gas at a pressure of 76 cm of mercury at a certain temperature. The mass of the gas is increased by 50% by introducing more gas in the vessel at the same temperature. The resultant pressure, in cm of Hg, is Show Answer

Q14) Statement 1 : Real gas approaches ideal gas behaviour for low pressure and low temperatures.
Statement 2 : At low pressure, density of gas is very low. Show Answer

Q15) Statement 1 : All molecules in a gas move with same speed.
Statement 2 : Average velocity of a gas sample is zero. Show Answer

Q16) What is the total kinetic energy of all the molecules of two gases before mixing? Show Answer

Q17) If T is the temperature of the mixture, then the total kinetic energy of the two gases after mixing is : Show Answer

Q18) The temperature T of the mixture is : Show Answer

Q19) The perfect gas equation for 4 gram of hydrogen gas is Show Answer

Q20) If the volume of the gas is to be increased by 4 times, Show Answer

Q21) In the kinetic theory of gases, which of these statements is/are true?
(i) The pressure of a gas is proportional to the mean speed of the molecules.
(ii) The root mean square speed of the molecules is proportional to the pressure.
(iii) The rate of diffusion is proportional to the mean speed of the molecules.
(iv) The mean translational kinetic energy of a gas is proportional to its Kelvin temperature. Show Answer

Q22) The rms speed of a gas molecule is Show Answer

Q23) According to kinetic theory of gases, at absolute zero of temperature, Show Answer

Q24) Which of the following statements is not in accordance with the assumptions made in kinetic theory? Show Answer

Q25) The X-components of velocities of some particles (in km//s) came to be 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10. The root mean square (rms) velocity calculated from these data (in km/s) is nearest to Show Answer

Q26) The average kinetic energy of hydrogen molecules at NTP is Show Answer

Q27) The temperature at which rms velocity of helium molecules is equal to the rms velocity of hydrogen molecules at NTP, is Show Answer

Q28) Statement 1 : If we compress a gas sample kept in a container, pressure increases.
Statement 2 : Frequency of collisions of atoms increases. Show Answer

Q29) Statement 1 : Internal energy of a gas sample is total kinetic energy of gas.
Statement 2 : There is no interaction force between gas molecules hence potential energy is not defined. Show Answer

Q30) Momentum transferred to wall in one collision is Show Answer

Q31) Which of the following is not true for a gas sample? Show Answer

Q32) Every gas (real gas) behaves as an ideal gas Show Answer

Q33) Boyle's law holds for an ideal gas during Show Answer

Q34) At absolute zero temperature, pressure of a gas will be Show Answer

Q35) The gas which obeys Boyle's law for maximum range of temperature is Show Answer

Q36) The temperature below which a gas should be cooled, before it can be liquified by pressure only is termed as Show Answer

Q37) It is possible for a substance to coexist in all three phases in equilibrium, when the substance is at Show Answer

Q38) When air is filled in the balloon, the pressure and volume both increases while temperature does not change. Here Boyle's law is not obeyed because Show Answer

Q39) For Boyle's law to hold the gas should be Show Answer

Q40) If a Vander-Waal's gas expands freely, then final temperature is Show Answer

Q41) At NTP, sample of equal volume of chlorine and oxygen is taken. Now ratio of No. of molecules Show Answer

Q42) Volume of gas become four times if Show Answer

Q43) At constant temperature on increasing the pressure of a gas by 5% will decrease its volume by Show Answer

Q44) Which law states that effect of pressure is same for all portion Show Answer

Q45) When the pressure on 1200 ml of a gas in increased from 70 cm to 120 cm of mercury at constant temperature, the new volume of the gas will be Show Answer

Q46) Under which of the following conditions is the law PV = RT obeyed most closely by a real gas Show Answer

Q47) That gas cannot be liquified Show Answer

Q48) At NTP the mass of one litre of air is 1.293 gm. The value of specific gas constant will be Show Answer

Q49) For one gram mol of a gas, the value of R in the equation PV = RT is nearly Show Answer

Q50) We write the relation for Boyle's law in the form PV = C when the temperature remains constant. In this relation, the magnitude of C depends upon Show Answer

Q51) A sample of an ideal gas occupies a volume V at a pressure P and absolute temperature T, the mass of each molecule is m. The expression for the density of gas is (k = Boltzmann’s constant) Show Answer

Q52) For ideal gas, which statement is not true Show Answer

Q53) Kinetic theory of gases was put forward by Show Answer

Q54) The equation of state for 5 g of oxygen at a pressure P and temperature T, when occupying a volume V, will be Show Answer

Q55) The pressure and temperature of two different gases is P and T having the volume V for each. They are mixed keeping the same volume and temperature, the pressure of the mixture will be Show Answer

Q56) At a given volume and temperature, the pressure of a gas Show Answer

Q57) The rate of diffusion is Show Answer

Q58) For matter to exist simultaneously in gas and liquid phases Show Answer

Q59) The value of critical temperature in terms of Vander Waal’s constant a and b is Show Answer

Q60) Air is filled in a bottle at atmospheric pressure and it is corked at 35°C. If the cork can come out at 3 atmospheric pressure than upto what temperature should the bottle be heated in order to remove the cork Show Answer

Q61) 125 ml of gas A at 0.60 atmosphere and 150 ml of gas B at 0.80 atmosphere pressure at same temperature is filled in a vessel of 1 litre volume. What will be the total pressure of mixture at the same temperature Show Answer

Q62) Saturated vapour is compressed to half its volume without any change in temperature, then the pressure will be Show Answer

Q63) What is the mass of 2 litres of nitrogen at 22.4 atmospheric pressure and 273K Show Answer

Q64) The value of PV/T for one mole of an ideal gas is nearly equal to Show Answer

Q65) A tyre kept outside in sunlight bursts off after sometime because of Show Answer

Q66) In Boyle's law what remains constant Show Answer

Q67) The r.m.s. velocity will be greater for Show Answer

Q68) In thermal equilibrium, the average velocity of gas molecules is Show Answer

Q69) For a gas, the r.m.s. speed at 800 K is Show Answer

Q70) The root mean square velocity of a gas molecule of mass m at a given temperature is proportional to Show Answer

Q71) A gas is allowed to expand isothermally. The root mean square velocity of the molecules Show Answer

Q72) Moon has no atmosphere because Show Answer

Q73) Which of the following statement is true Show Answer

Q74) Two vessels having equal volume contains molecular hydrogen at one atmosphere and helium at two atmospheres respectively. If both samples are at the same temperature, the mean velocity of hydrogen molecules is Show Answer

Q75) The temperature of an ideal gas is increased from 120 K to 480 K. If at 120 K, the root mean square velocity of the gas molecules is v, at 480 K it becomes Show Answer

Q76) At a given temperature the r.m.s. velocity of molecules of the gas is Show Answer

Q77) The speeds of 5 molecules of a gas (in arbitrary units) are as follows : 2, 3, 4, 5, 6. The root mean square speed for these molecules is Show Answer

Q78) The r.m.s. speed of a group of 7 gas molecules having speeds (6, 4, 2, 0, – 2, – 4, – 6) m/s is Show Answer

Q79) Molecular motion shows itself as Show Answer

Q80) According to the kinetic theory of gases, at absolute temperature Show Answer

Q81) If the pressure in a closed vessel is reduced by drawing out some gas, the mean free path of the molecules Show Answer

Q82) At constant volume, temperature is increased. Then Show Answer

Q83) At constant volume, for different diatomic gases the molar specific heat is Show Answer

Q84) The specific heats at constant pressure is greater than that of the same gas at constant volume because

Show Answer

Q85) Which of the following formulae is wrong Show Answer

Q86) The quantity of heat required to raise one mole through one degree Kelvin for a monoatomic gas at constant volume is Show Answer

Q87) If two moles of diatomic gas and one mole of mono atomic gas are mixed then the ratio of specific heats is

Show Answer

Q88) The kinetic energy, due to translational motion, of most of the molecules of an ideal gas at absolute temperature T is Show Answer

Q89) The ratio of specific heat of a mixture of one mole of helium and one mole of hydrogen gas will be Show Answer

Q90) If a gas has n degrees of freedom ratio of specific heats of gas is Show Answer

Q91) The degrees of freedom of a stationary rigid body about its axis will be Show Answer

Q92) The pressure exerted by the gas on the walls of the container because Show Answer

Q93) In kinetic theory of gases, a molecule of mass m of an ideal gas collides with a wall of vessel with velocity V. The change in the linear momentum of the molecule is Show Answer

Q94) Relationship between and for a gas is Show Answer

Q95) According to the kinetic theory of gases, total energy of a gas is equal to Show Answer

Q96) Mean kinetic energy (or average energy) per gm molecule of a monoatomic gas is given by Show Answer

Q97) The time average of the kinetic energy of one molecule of a gas taken over a long period of time Show Answer

Q98) The kinetic energy per gm mol for a diatomic gas at room temperature is Show Answer

Q99) The translatory kinetic energy of a gas per gm is Show Answer

Q100) Read the given statements and decide which is/are correct on the basis of kinetic theory of gases [MP PMT 2003]
(I) Energy of one molecule at absolute temperature is zero
(II) r.m.s. speeds of different gases are same at same temperature
(III) For one gram of all ideal gas kinetic energy is same at same temperature
(IV) For one mole of all ideal gases mean kinetic energy is same at same temperature
Show Answer

Q101) At the same temperature and pressure and volume of two gases, which of the following quantities is constant Show Answer

Q102) On absolute temperature, the kinetic energy of the molecules Show Answer

Q103) On colliding in a closed container the gas molecules Show Answer

Q104) The molecules of an ideal gas at a certain temperature have Show Answer

Q105) From the following statements, concerning ideal gas at any given temperature T, select the correct one(s) Show Answer

Q106) A gas in container A is in thermal equilibrium with another gas in container B. both contain equal masses of the two gases in the respective containers. Which of the following can be true Show Answer

Q107) A closed vessel contains 8gm of oxygen and 7gm of nitrogen. The total pressure is 10 atm at a given temperature. If now oxygen is absorbed by introducing a suitable absorbent the pressure of the remaining gas in atm will be Show Answer

Q108) If the intermolecular forces vanish away, the volume occupied by the molecules contained in 4.5 kg water at standard temperature and pressure will be Show Answer

Q109) The temperature at which the r.m.s. speed of hydrogen molecules is equal to escape velocity on earth surface, will be Show Answer

Q110) Inside a cylinder having insulating walls and closed at ends is a movable piston, which divides the cylinder into two compartments. On one side of the piston is a mass m of a gas and on the other side a mass 2 m of the same gas. What fraction of volume of the cylinder will be occupied by the larger mass of the gas when the piston is in equilibrium ? Consider that the movable piston is conducting so that the temperature is the same throughout Show Answer

Q111) A gas mixture consists of 2 mole of oxygen and 4 mole of argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is Show Answer

Q112) Which one the following graphs represents the behaviour of an ideal gas Show Answer

Q113) Assertion : In pressure-temperature (P-T) phase diagram of water, the slope of the melting curve is found to be negative.
Reason : Ice contracts on melting to water.
Show Answer

Q114) Assertion :Equal masses of helium and oxygen gases are given equal quantities of heat. There will be a greater rise in the temperature of helium compared to that of oxygen.
Reason :The molecular weight of oxygen is more than the molecular weight of helium.
Show Answer

Q115) Assertion :Absolute zero is the temperature corresponding to zero energy.
Reason :The temperature at which no molecular motion cease is called absolute zero temperature.
Show Answer

Q116) The rate of cooling at 600 K, if surrounding temperature is 300 K is. The rate of cooling at 900 K is Show Answer

Q117) A diatomic molecule has how many degrees of freedom Show Answer

Q118) The temperature at which the average translational kinetic energy of a molecule is equal to the energy gained by an electron in accelerating from rest through a potential difference of 1 volt is Show Answer

Q119) The latent heat of vaporization of water is 2240 J. If the work done in the process of vaporization of 1 g is 168 J, then increase in internal energy is Show Answer

Q120) In the absence of intermolecular forces of attraction, the observed pressure p will be Show Answer

Q121) What is the mass of 2 L of nitrogen at 22.4 atm pressure and 273 K? Show Answer

Q122) The root mean square velocity of a gas molecule of mass m at a given temperature is proportional to Show Answer

Q123) The ratio of the molar heat capacities of a diatomic gas at constant pressure to that at constant volume is Show Answer

Q124) The specific heat of an ideal gas is Show Answer

Q125) Pressure of an ideal gas is increased by keeping temperature constant. What is the effect on kinetic energy of molecules? Show Answer

Q126) A monoatomic gas molecule has Show Answer

Q127) The vapour of a substance behaves as a gas Show Answer

Q128) The molecular weight of a gas is 44. The volume occupied by 2.2 g of this gas at 0℃ and 2 atm. pressure will be Show Answer

Q129) The temperature of a gas is -68℃. At what temperature will the average kinetic energy of its molecules be twice that of at -68℃? Show Answer

Q130) A vertical column 50 cm long at 50℃ balances another column of liquid 60 cm long at 100℃. The coefficient of absolute expansion of the liquid is Show Answer

Q131) Consider a collection of a large number of particles each with speed v. The direction of velocity is randomly distributed in the collection. What is the magnitude of the relative velocity between a pairs in the collection Show Answer

Q132) The translational kinetic energy of gas molecule for one mole of the gas is equal to Show Answer

Q133) Cooking gas containers are kept in a lorry moving with uniform speed. The temperature of the gas molecules inside will Show Answer

Q134) If temperature of gas increases from 27℃ to 927℃ the K.E. will be Show Answer

Q135) For an ideal gas Show Answer

Q136) The average kinetic energy of hydrogen molecules at 300 K is E. At the same temperature, the average kinetic energy of oxygen molecules will be Show Answer

Q137) The r.m.s. speed of gas molecules is given by Show Answer

Q138) A box contains n molecules of a gas. How will the pressure of the gas be effected, if the number of molecules is made 2n Show Answer

Q139) Root mean square velocity of a particle is v at pressure P. If pressure is increased two times, then the r.m.s. velocity becomes Show Answer

Q140) The amount of heat required to convert 10 g of ice at -10℃ into steam at 100℃ is (in calories) Show Answer

Q141) The absolute temperature of a gas is determined by Show Answer

Q142) It is seen that in proper ventilation of building, windows must be opened near the bottom and the top of the walls, so as to let pass Show Answer

Q143) A container with insulating walls is divided into two equal parts by a partition fitted with a value. One part is filled with an ideal gas at a pressure p and temperature T, whereas the other part is completely evacuated. If the valve is suddenly opened, the pressure and temperature of the gas will be Show Answer

Q144) The mean kinetic energy of one mole of gas per degree of freedom (on the basis of kinetic theory of gases) is Show Answer

Q145) A polyatomic gas with n degrees of freedom has a mean energy per molecule given by
(N is Avogadro’s number)
Show Answer

Q146) Two spheres made of same substance have diameters in the ratio1∶2. Their thermal capacities are in the ratio of Show Answer

Q147) Volume of gas becomes four times if Show Answer

Q148) 22 g of carbon dioxide at 27℃ is mixed in a closed container with 16 g of oxygen at 37℃. If both gases are considered as ideal gases, then the temperature of the mixture is Show Answer

Q149) The molar specific heat at constant pressure of an ideal gas is (7/2)R. The ratio of specific heat at constant pressure to that at constant volume is Show Answer

Q150) The efficiency of a Carnot engine is 50% and temperature of sink is 500 K. If temperature of source is kept constant and its efficiency raised to 60%, then the required temperature of sink will be Show Answer

Q151) A steel ball of mass 0.1 kg falls freely from a height of 10 m of 10 m and bounces to a height of 5.4 m from the ground. If the dissipated energy in this process is absorbed by the ball, the rise in its temperature is Show Answer

Q152) At 0 K which of the following properties of a gas will be zero Show Answer

Q153) For ideal gas, which statement is not true Show Answer

Q154) Under constant temperature, graph between P and 1/V is Show Answer

Q155) A jar contains a gas and few drops of water at T K. The pressure in the jar is 830 mm of mercury. The temperature of jar is reduced by 1%. The saturated vapour pressure of water at the two temperatures are 30 mm and 25 mm of mercury. Then the new pressure in the jar will be Show Answer

Q156) On 0℃ pressure measured by barometer is 760 mm. What will be pressure at 100℃ Show Answer

Q157) KE per unit volume is E. The pressure exerted by the gas is given by Show Answer

Q158) A cylinder of 5 litre capacity, filled with air at N.T.P. is connected with another evacuated cylinder of 30 litres of capacity. The resultant air pressure in both the cylinders will be Show Answer

Q159) Boyle’s law holds for an ideal gas during Show Answer

Q160) The temperature of argon, kept in a vessel, is raised by 1℃ at a constant volume. The total heat supplied to the gas is a combination of translation and rotational energies. Their respective shares are Show Answer

Q161) The kinetic energy, due to translation motion, of most of the molecules of an ideal gas at absolute temperature T is Show Answer

Q162) At temperature T, the r.m.s. speed of helium molecules is the same as r.m.s. speed of hydrogen molecules at normal temperature and pressure. The value of T is Show Answer

Q163) The temperature of a gas contained in a closed vessel of constant volume increases by 1℃ when the pressure of the gas is increased by 1%. The initial temperature of the gas is Show Answer

Q164) In Boyle’s law what remains constant Show Answer

Q165) The degrees of freedom of a molecule of a triatomic gas are Show Answer

Q166) A sealed container with negligible coefficient of volumetric expansion contains helium (a monoatomic gas). When it is heated from 300 K to 600 K, the average K.E. of helium atoms is Show Answer

Q167) Equation of gas in terms of pressure (P), absolute temperature (T) and density (d) is Show Answer

Q168) Air is filled in a bottle at atmospheric pressure and it is corked at 35℃. If the cork can come out at 3 atmospheric pressure than upto what temperature should the bottle be heated in order to remove the cork Show Answer

Q169) The kinetic energy of translation of 20 g of oxygen at 47℃ is (molecular wt. of oxygen is 32 g/mol and R = 8.3J/mol/K) Show Answer

Q170) If a Vander-Waal’s gas expands freely, then final temperature is Show Answer

Q171) To what temperature should the hydrogen at room temperature (27℃) be heated at constant pressure so that the R.M.S. velocity of its molecules becomes double of its previous value Show Answer

Q172) The temperature of the hydrogen at which the average speed of its molecules is equal to that of oxygen molecules at a temperature of 31℃, is Show Answer

Q173) The pressure is exerted by the gas on the walls of the container because Show Answer

Q174) For one gram mol of a gas, the value of R in the equation PV=RT is nearly Show Answer

Q175) One mole of a monoatomic ideal gas is mixed with one mole of a diatomic ideal gas. The molar specific heat of the mixture at constant volume is Show Answer

Q176) In thermal equilibrium, the average velocity of gas molecules is Show Answer

Q177) The heat capacity per mole of water is (R is universal gas constant) Show Answer

Q178) Oxygen and hydrogen are at the same temperature T . The ratio of the mean kinetic energy of oxygen molecules to that of the hydrogen molecules will be Show Answer

Q179) One litre of oxygen at a pressure of 1 atm and two litres of nitrogen at a pressure of 0.5 atm, are introduced into a vessel of volume 1 L. If there is no change in temperature, the final pressure of the mixture of gas (in atm) is Show Answer

Q180) Molecules of a gas behave like Show Answer

Q181) For an ideal gas of diatomic molecules Show Answer

Q182) Oxygen boils at (-183℃). The temperature on the Fahrenheit scale is Show Answer

Q183) Which one of the following graphs represents the behaviour of an ideal gas? Show Answer

Q184) A gas at 27℃ has a volume V and pressure P. On heating its pressure is doubled and volume becomes three times. The resulting temperature of the gas will be Show Answer

Q185) S.I. unit of universal gas constant is Show Answer

Q186) At 100 K and 0.1 atmospheric pressure, the volume of helium gas is 10 litres. If volume and pressure are doubled, its temperature will change to Show Answer

Q187) A gas is filled in a cylinder, its temperature is increased by 20% on kelvin scale and volume is reduced by 10%. How much percentage of the gas will leak out Show Answer

Q188) A gas mixture consists of 2 moles of oxygen and 4 moles of argon at temperature T. Neglecting all vibrational moles, the total internal energy of the system is Show Answer

Q189) A sample of gas is at 0℃. To what temperature it must be raised in order to double the r.m.s. speed of the molecule Show Answer

Q190) A cylinder rolls without slipping down an inclined plane, the number of degrees of freedom it has, is Show Answer

Q191) When the temperature of a gas is raised from 27℃ to 90℃, the percentage increase in the r.m.s. velocity of the molecules will be Show Answer

Q192) At a given temperature the ratio of r.m.s. velocities of hydrogen molecule and helium atom will be Show Answer

Q193) Root mean square speed of the molecules of ideal gas is v. If pressure is increased two times at
constant temperature, the rms speed will become Show Answer

Q194) For a gas, the r.m.s. speed at 800 K is Show Answer

Q195) At NTP, sample of equal volume of chlorine and oxygen is taken. Now ratio of no. of molecules is Show Answer

Q196) If masses of all molecules of a gas are halved and their speeds are doubles, then the ratio of initial
and final pressures is Show Answer

Q197) The pressure and temperature of two different gases is P and T having the volume V for each. They are
mixed keeping the same volume and temperature, the pressure of the mixture will be Show Answer

Q198) The molar specific heat at constant pressure for a monoatomic gas is Show Answer

Q199) The ratio of mean kinetic energy of hydrogen and oxygen at a given temperature is Show Answer

Q200) 310 J of heat is required to raise the temperature of 2 mole of an ideal gas at constant pressure from 25°C
to 35°C. The amount of heat required to raise the temperature of the gas through the same range at
constant volume is Show Answer

Q201) Which of the following cylindrical rods will conduct maximum heat,when their ends are maintained at a
constant temperature difference? Show Answer

Q202) The temperature of a piece of metal is increased from 27°C to 84°C. The rate at which energy is radiated is
increased to Show Answer

Q203) A closed gas cylinder is divided into two parts by a piston held tight. The pressure and volume of gas in two parts respectively are (P,5V) and (10P,V). If now the piston is left free and the system undergoes
is on thermal process, then the volume of the gas in two parts respectively are Show Answer

Q204) Temperature remaining constant, the pressure of gas is decreased by 20%. The percentage
change in volume Show Answer

Q205) Volume-temperature graph at atmospheric pressure for a monoatomic gas (V in m³,T in ℃) is

Show Answer

Q206) If the volume of the gas containing n number of molecules is V, then the pressure will decrease due to force of intermolecular attraction in the proportion Show Answer

Q207) The average momentum of a molecule in an ideal gas depends on Show Answer

Q208) Six molecules speeds 2 unit, 5 unit, 3 unit, 6 unit, 3 unit, and 5 unit respectively. The rms speed is Show Answer

Q209) Speed of sound in a gas is v and r.m.s. velocity of the gas molecules is c. The ratio of v to c is Show Answer

Q210) At what temperature the molecule of nitrogen will have same rms velocity as the molecule of oxygen at 127℃ ? Show Answer

Q211) Mean kinetic energy (or average energy) per g molecule of a monoatomic gas is given by Show Answer

Q212) A body takes 10 min to cool from 60℃ to 50℃. If the temperature of surroundings is 25℃ and 527℃ respectively. The ratio of energy radiated by P and Q is Show Answer

Q213) Kinetic theory of gases provide a base for Show Answer

Q214) The temperature of an ideal gas is increased from 27℃ to 927℃. The root mean square speed of its molecules becomes Show Answer

Q215) The volume of a gas at 20℃ is 200 ml. If the temperature is reduced to -20℃ at constant pressure, its volume will be Show Answer

Q216) The temperature of an ideal gas is reduced from 927℃ to 27℃. The r.m.s. velocity of the molecules becomes Show Answer

Q217) According to the kinetic theory of gases, the temperature of a gas is a measure of average Show Answer

Q218) The tyre of a motor car contains air at 15℃ . If the temperature increases to 35℃ , the approximate percentage increase is (ignore to expansion of tyre) Show Answer

Q219) According to the kinetic theory of gases the r.m.s. velocity of gas molecules is directly proportional to Show Answer

Q220) Two moles of oxygen is mixed with eight moles of helium. The effective specific heat of the mixture at constant volume is Show Answer

Q221) What is the ratio of specific heats of constant pressure and constant volume for NH3 Show Answer

Q222) Which one of the following graph is correct at constant pressure Show Answer

Q223) The average kinetic energy of a gas molecule can be determined by knowing Show Answer

Q224) At what temperature the rms velocity of helium molecules will be equal to that of hydrogen molecules at NTP? Show Answer

Q225) The product of the pressure and volume of an ideal gas is Show Answer

Q226) A bubble is at the bottom of the lake of depth h. As the bubble comes to sea level, its radius increases three times. If atmospheric pressure is equal to l metre of water column, then h is equal to Show Answer

Q227) Two spheres made of same material have radii in the ratio1∶2. Both are at same temperature. Ratio of heat radiation energy emitted per second by them is Show Answer

Q228) A horizontal uniform glass tube of 100 cm length sealed at both ends contains 10 cm mercury column in the middle. The temperature and pressure of air on either side of mercury column are respectively 31℃ and 76 cm of mercury. If the air column at one end is kept at 0℃ and the other end at 273℃ , the pressure of air which is at 0℃ is (in cm of Hg) Show Answer

Q229) The relationship between pressure and the density of a gas expressed by Boyle’s law, P=KD holds true Show Answer

Q230) A closed vessel is maintained at a constant temperature. It is first evacuated and then vapour is injected into it continuously. The pressure of the vapour in the vessel Show Answer

Q231) Two balloons are filled, one with pure He gas and the other by air, respectively. If the pressure and temperature of these balloons are same, then the number of molecules per unit volume is Show Answer

Q232) A gas at the temperature 250 K is contained in a closed vessel. If the gas is heated through 1K, then the percentage increase in its pressure will be Show Answer

Q233) An ideal gas is filled in a vessel, then Show Answer

Q234) On giving equal amount of heat at constant volume to 1 mole of a monoatomic and a diatomic gas the rise in temperature Show Answer

Q235) At what temperature is the root mean square velocity of gaseous hydrogen molecules equal to that of oxygen molecules at 47℃ Show Answer

Q236) At what temperature the kinetic energy of gas molecule is half of the value at 27℃? Show Answer

Q237) If the temperature of an ideal gas increases three times, then its rms velocity will become Show Answer

Q238) A diatomic gas is heated at constant pressure. What fraction of the heat energy is used to increase the thermal energy Show Answer

Q239) If mass of He is 4 times that of hydrogen, then mean velocity of He is Show Answer

Q240) At what temperature rms speed of air molecules is doubled of that at NTP? Show Answer

Q241) Supposing the distance between the atoms of a diatomic gas to be constant, its specific heat at constant volume per mole (gram mole) is Show Answer

Q242) Which of the following formula is wrong Show Answer

Q243) If the mean free path of atoms is doubled then the pressure of gas will become Show Answer

Q244) The specific heat of a gas Show Answer

Q245) The root mean square speed of the molecules of a diatomic gas is v. When the temperature is doubled, the molecules dissociate into two atoms. The new root mean square speed of the atom is Show Answer

Q246) For a real gas (van der Waal’s gas) Show Answer

Q247) Graph of specific heat at constant volume for a monoatomic gas is Show Answer

Q248) The time average of the kinetic energy of one molecule of a gas taken over a long period of time Show Answer

Q249) The root mean square speed of the molecules of a gas is Show Answer

Q250) At constant pressure, which of the following is true? Show Answer

Q251) Two moles of monoatomic gas is mixed with three moles of a diatomic gas. The molar specific heat of the mixture at constant volume is Show Answer

Q252) At what temperature will the rms speed of air molecules be double than that at NTP? Show Answer

Q253) A perfect gas at 27℃ is heated at constant pressure to 327℃. If original volume of gas at 27℃ is V then volume at 327℃ is Show Answer

Q254) Universal gas constant is Show Answer

Q255) Which of the following statements about kinetic theory of gases is wrong Show Answer

Q256) At constant pressure, the ratio of increase in volume of an ideal gas per degree rise in kelvin temperature to it’s original volume is (T= absolute temperature of the gas) Show Answer

Q257) The temperature of a given mass is increased from 27℃ to 327℃ . The rms velocity of the molecules increases Show Answer

Q258) Mean kinetic energy per degree of freedom of gas molecules is Show Answer

Q259) The specific heat relation for ideal gas is Show Answer

Q260) A gas at 27℃ temperature and 30 atmospheric pressure is allowed to expand to the atmospheric pressure. If the volume becomes 10 times its initial volume, then the final temperature becomes Show Answer

Q261) Volume, pressure and temperature of an ideal gas are V,P and T respectively. If mass of its molecule is m, then its density is [k= boltzmann’s constant] Show Answer

Q262) A vessel of volume 4 L contains a mixture of 8 g of oxygen, 14 g of nitrogen and 22 g of carbon dioxide at 27℃. The pressure exerted by the mixture is Show Answer

Q263) In kinetic theory of gases, which of the following statements regarding elastic collisions of the molecules is wrong Show Answer

Q264) The mean kinetic energy of a gas at 300 K is 100 J. The mean energy of the gas at 450 K is equal to Show Answer

Q265) One mole of an ideal monoatomic gas requires 210 J heat to raise the temperature by 10K, when heated at constant temperature. If the same gas is heated at constant volume to raise the temperature by 10K then heat required is Show Answer

Q266) At a given temperature the root mean square velocities of oxygen and hydrogen molecules are in the ratio Show Answer

Q267) What is an ideal gas? Show Answer

Q268) A gas is allowed to expand isothermally. The root mean square velocity of the molecules Show Answer

Q269) Saturated vapour is compressed to half is volume without any change in temperature, then the pressure will be Show Answer

Q270) The average kinetic energy of a gas molecules is Show Answer

Q271) Calculate the ratio of rms speeds of oxygen gas molecules to that of hydrogen gas molecules kept at the same temperature Show Answer

Q272) If mass of He atom is 4 times that of hydrogen then mean velocity of He is Show Answer

Q273) The ratio of the vapour densities of two gases at a given temperature is 9:8. The ratio of the rms velocities of their molecules is Show Answer

Q274) A gas is collected over the water at 25℃. The total pressure of moist gas was 735 mm of mercury. If the aqueous vapour pressure at 25℃ is23.8 mm. Then the pressure of dry gas is Show Answer

Q275) 125 ml of gas A at 0.60 atmosphere and 150 ml of gas B at 0.80 atmospheric pressure at same temperature is filled in a vessel of 1 litre volume. What will be the total pressure of mixture at the same temperature Show Answer

Q276) The kinetic energy per gmol for a diatomic gas at room temperature is Show Answer

Q277) A gas is filled in a closed container and its molecules are moving in horizontal direction with uniform acceleration. Neglecting acceleration due to gravity, the pressure inside the container is Show Answer

Q278) The rate of diffusion is Show Answer

Q279) r.m.s. velocity of nitrogen molecules at NTP is Show Answer

Q280) Mean free path of a gas molecule is Show Answer

Q281) If universal gas constant is R, the essential heat to increase from 273 K to 473 K at constant volume for ideal gas of 4 mol is Show Answer

Q282) According to Maxwell’s law of distribution of velocities of molecules, the most probable velocity is Show Answer

Q283) The equation for an ideal gas is PV=RT, where V represents the volume of Show Answer

Q284) At the same temperature and pressure and volume of two gases, which of the following quantities is
constant Show Answer

Q285) A closed compartment containing gas is moving with some acceleration in horizontal direction. Neglect effect of gravity. Then the pressure in the compartment is Show Answer

Q286) Vapour is injected at a uniform rate in a closed vessel which was initially evacuated. The pressure in the vessel Show Answer

Q287) According to the kinetic theory of gases, at absolute temperature Show Answer

Q288) For a diatomic gas change in internal energy for unit change in temperature for constant volume is U1 and
U2 respectively. U1:U2 is Show Answer

Q289) When volume of system is increased two times and temperature is decreased half of its initial temperature, then pressure becomes Show Answer

Q290) The relation between two specific heats of a gas is Show Answer

Q291) The quantity of heat required to raise one mole through one degree kelvin for a mono atomic gas at
constant volume is Show Answer

Q292) The temperature at which the kinetic energy of oxygen molecules becomes double than its value at 27°C is Show Answer

Q293) A gas mixture consists of 2 moles of oxygen and 4 moles of neon at temperature T. Neglecting all vibrational modes, the total internal energy of the system will be. Show Answer

Q294) Given below are two statements.
Statement I The temperature of a gas is - 73°C. When the gas is heated to 527°C, the root mean square speed of the molecules is doubled. Statement II The product of pressure and volume of an ideal gas will be equal to translational kinetic energy of the molecules. [2023, 24 Jan Shift-1] In the light of the above statements, choose the correct answer from the options given below. Show Answer

Q295) The root mean square velocity of molecules of gas is
Show Answer

Q296) Given below are two statements.
Statement I The average momentum of a molecule in a sample of an ideal gas depends on temperature. Statement II The rms speed of oxygen molecules in a gas is v. If the temperature is doubled and the oxygen speed will become 2 v. molecules dissociate into oxygen atoms, the rms
In the light of the above statements, choose the correct answer from the options given below. Show Answer

Q297) Same gas is filled in two vessels of the same volume a the same temperature. If the ratio of the number of molecules is 1:4, then
A. The rms velocity of gas molecules in two vessels will be the same.
B. The ratio of pressure in these vessels will be 1 : 4. C. The ratio of pressure will be
1:1.
D. The rms velocity of gas molecules in two vessels will be in the ratio of 1: 4.
Choose the correct answer from the options given below. Show Answer

Q298) Sound travels in a mixture of two moles of helium and n moles of hydrogen. If rms speed of gas molecules in the mixture is √2 times the speed of sound, then the value of n will be Show Answer

Q299) Following statements are given.
(A) The average kinetic energy decreases when the temperature is reduced. (B) The average kinetic energy of a gas molecule increases with increase in pressure at constant temperature.
(C) The average kinetic energy of a gas molecule decreases with increase in volume.
(D) Pressure of a gas increases with increase in temperature at constant volume.
(E) The volume of gas decreases with increase in temperature.
Choose the correct answer from the options given below. Show Answer

Q300) What will be the effect on the root mean square velocity of oxygen molecules, if the temperature is doubled and oxygen molecule dissociates into atomic oxygen? Show Answer

Q301) A flask contains argon and oxygen in the ratio of 3:2 in mass and the mixture is kept at 27°C. The ratio of their average kinetic energy per molecule respectively, will be Show Answer

Q302) A thermally insulated vessel contains an ideal gas of molecular mass M and ratio of specific heats is 1.4. Vessel is moving with speed v and is suddenly brought to rest. Assuming no heat is lost to the surrounding and vessel, temperature of the gas increases by (where, R = universal gas constant) Show Answer

Q303) The pressure of the gas in a constant volume gas thermometer is 100 cm of mercury when placed in melting ice at 1 atm. When the bulb is placed in a liquid, the pressure becomes 180 cm of mercury. Temperature of the liquid is (Given 0°C = 273 K) Show Answer

Q304) If the rms speed of oxygen molecules at 0°C is 160 m/s, find the rms speed of hydrogen molecules at 0°C. Show Answer

Q305) A balloon carries a total load of 185 kg at normal pressure and temperature of 27°C. What load will the balloon carry on rising to a height at which the barometric pressure is 45 cm of Hg and the temperature is -7°C? [Assuming, the volume constant.] Show Answer

Q306) Which of the following graphs represent behaviour of an ideal gas? (Symbols have their usual meanings.) Show Answer

Q307) On the basis of kinetic theory of gases, the gas exerts pressure because its molecules Show Answer

Q308) In a dilute gas at pressure p and temperature T, the mean time between successive collisions of a molecule varies with T as Show Answer

Q309) An ideal gas in a closed container is slowly heated. As its temperature increases, which of the following statements are true?
A. The mean free path of the molecules decreases. B. The mean collision time between the molecules decreases.
C. The mean free path remains unchanged.
D. The mean collision time remains unchanged. Show Answer

Q310) Two moles of helium gas is mixed with three moles of hydrogen molecules (taken to be rigid). What is the molar specific heat of mixture at constant volume? [Take, R = 83 J/mol-K] Show Answer

Q311) A diatomic gas with rigid molecules does 10 J of work when expanded at constant pressure. What would be the heat energy absorbed by the gas, in this process? Show Answer

Q312) For a given gas at 1 atm pressure, rms speed of the molecules is 200 m/s at 127° C. At 2 atm pressure and at 227° C, the rms speed of the molecules will be Show Answer

Q313) Half-mole of an ideal monoatomic gas is heated at o constant pressure of 1 atm from 20°C to 90°C. 01 Work done by gas is close to (Take, gas constant, R=831J/mol-K) Show Answer

Q314) An open glass tube is immersed in mercury in such a way that a length of 8 cm extends above the mercury level. The open end of the tube is then closed and sealed and the tube is raised vertically up by additional 46 cm. What will be length of the air column above mercury in the tube now? (Atmospheric pressure = 76 cm of Hg) Show Answer

Q315) A container with insulating walls is divided into two equal parts by a partition fitted with a valve. One part is filled with an ideal gas at a pressure p and temperature T, whereas the other part is completely evacuated. If the valve is suddenly opened, the pressure and temperature of the gas will be Show Answer

Q316) Cooking gas containers are kept in a lorry moving with uniform speed. The temperature of the gas molecules inside will
Show Answer

Q317) A monoatomic gas performs work of Q/4, where Q is the heat supplied to it. The molar heat capacity of the gas will be...... R during this transformation. (where, R is the gas constant.) Show Answer

Q318) The mean free path of molecules of a certain STP is 1500d, where d is the diameter of the molecules. While maintaining the standard the mean free path of the molecules at 373K is approximately mean?

Show Answer

Q319) Heat energy of 735 J is given to a diatomic gas allowing the gas to expand at constant pressure. Each gas molecule rotates around an internal axis but do not oscillate. The increase in the internal of energy the gas will be
Show Answer

Q320) According to law of equipartition of energy the molar specific heat of a diatomic gas at constant volume where the molecule has one additional vibrational mode is
Show Answer

Q321) Which statements are correct about degrees of freedom?
A. A molecule with n degrees of freedom has n different ways of storing energy.
B. Each degree of freedom is associated with RT is average energy per mole.
C. A monoatomic gas molecule has 1 rotational degree of freedom whereas diatomic molecule has 2 rotational degrees of freedom.
D. CH4 has a total of 6 degrees of freedom. Choose the correct answer from the option given below.
Show Answer

Q322) A gas has n degrees of freedom. The ratio of specific heat of gas at constant volume to the specific heat of gas at constant pressure will be Show Answer

Q323) Following statements are given.
decreases when the temperature is reduced. (B) The average kinetic energy of a gas molecule
increases with increase in temperature.
pressure at constant
(C) The average kinetic energy of a gas molecule
decreases with increase in volume.
(D) Pressure of a gas increases with increase in temperature at constant pressure.
(E) The volume of gas decreases with increase in temperature.
Choose the correct answer from the options given below.
Show Answer

Q324) What will be the average value of energy for a 28 monoatomic gas in thermal equilibrium at
temperature T?
Show Answer

Q325) The internal energy (U), pressure (p) and volume (V) of an ideal gas are related as U=3 pV +4. The gas is

Show Answer

Q326) Given below are two statements:
Statement I In a diatomic molecule, the rotational energy at a given temperature obeys Maxwell's
distribution.
Statement II In a diatomic molecule, the rotational energy at a given temperature equals the translational kinetic energy for each molecule.
In the light of the above statements, choose the correct answer from the options given below.
Show Answer

Q327) A gas gas mixture consists of 3 moles of oxygen and 5 moles of argon at temperature T. Assuming the gases to be ideal and the oxygen bond to be rigid, the total internal energy (in units of RT) of the mixture is Show Answer

Q328) Two moles of an ideal monoatomic gas occupies a volume V at 27° C. The gas expands adiabatically a volume 2 V. Calculate (I) the final temperature of the gas and (II) change in its internal energy. Show Answer

Q329) The total internal energy of two mole monoatomic ideal gas at temperature, T = 300 K will be .......... (Given, R = 8.31 J/mol K) Show Answer

Q330) An engine takes in 5 moles of air at 20° C and 1 atm (and compresses it adiabatically to 1/10th of the original volume. Assuming air to be a diatomic ideal made of rigid molecules, the change in its up internal energy during this process comes out to be XkJ. The value of X to the nearest integer is .... Show Answer