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

2) The SI unit of thermal conductivity (K) is

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

4) 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

5) Estimate the ratio of their number of molecules.

6) Estimate the mass densities of Neon to Oxygen in vessel.

7) Obtain the ratio of average kinetic energy per molecule of argon to chlorine.

8) 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?

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

10) Boyle's law is applicable in

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

12) 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

13) 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

14) 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.

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

16) What is the total kinetic energy of all the molecules of two gases before mixing?

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

18) The temperature T of the mixture is :

19) The perfect gas equation for 4 gram of hydrogen gas is

20) If the volume of the gas is to be increased by 4 times,

21) 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.

22) The rms speed of a gas molecule is

23) According to kinetic theory of gases, at absolute zero of temperature,

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

25) 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

26) The average kinetic energy of hydrogen molecules at NTP is

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

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

29) 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.

30) Momentum transferred to wall in one collision is

31) Which of the following is not true for a gas sample?

32) Every gas (real gas) behaves as an ideal gas

33) Boyle's law holds for an ideal gas during

34) S.I. unit of universal gas constant is

35) Molecules of a gas behave like

36) At absolute zero temperature, pressure of a gas will be

37) The gas which obeys Boyle's law for maximum range of temperature is

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

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

40) 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

41) For Boyle's law to hold the gas should be

42) Which of the following statements about kinetic theory of gases is wrong

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

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

45) 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

46) 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

47) Volume of gas become four times if

48) Kinetic theory of gases provide a base for

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

50) Which law states that effect of pressure is same for all portion

51) 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

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

53) That gas cannot be liquified

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

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

56) 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

57) 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 = Boltzmannâ€™s constant)

58) The product of the pressure and volume of an ideal gas is

59) For ideal gas, which statement is not true

60) Kinetic theory of gases was put forward by

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

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

63) 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

64) At a given volume and temperature, the pressure of a gas

65) The rate of diffusion is

66) For matter to exist simultaneously in gas and liquid phases

67) The value of critical temperature in terms of Vander Waalâ€™s constant a and b is

68) Air is filled in a bottle at atmospheric pressure and it is corked at 35Â°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

69) 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

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

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

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

73) A tyre kept outside in sunlight bursts off after sometime because of

74) In Boyle's law what remains constant

75) In Boyle's law what remains constant

76) The r.m.s. velocity will be greater for

77) In thermal equilibrium, the average velocity of gas molecules is

78) The absolute temperature of a gas is determined by

79) For a gas, the r.m.s. speed at 800 K is

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

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

82) Moon has no atmosphere because

83) 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

84) Which of the following statement is true

85) 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

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

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

88) r.m.s. velocity of nitrogen molecules at NTP is

89) 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

90) The root mean square speed of the molecules of a gas is

91) At a given temperature the r.m.s. velocity of molecules of the gas is

92) 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

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

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

95) The r.m.s. speed of a group of 7 gas molecules having speeds (6, 4, 2, 0, â€“ 2, â€“ 4, â€“ 6) m/s is

96) Molecular motion shows itself as

97) According to the kinetic theory of gases, at absolute temperature

98) The r.m.s. speed of gas molecules is given by

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

100) At constant volume, temperature is increased. Then

101) A monoatomic gas molecule has

102) For an ideal gas of diatomic molecules

103) At constant volume, for different diatomic gases the molar specific heat is

104) The specific heat of an ideal gas is

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

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

107) The specific heat of a gas

108) The molar specific heat at constant pressure for a monoatomic gas is

109) Which of the following formulae is wrong

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

111) The specific heat relation for ideal gas is

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

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

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

115) If a gas has n degrees of freedom ratio of specific heats of gas is

116) The degrees of freedom of a stationary rigid body about its axis will be

117) The pressure exerted by the gas on the walls of the container because

118) 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

119) If the mean free path of atoms is doubled then the pressure of gas will become

120) Relationship between and for a gas is

121) The ratio of mean kinetic energy of hydrogen and oxygen at a given temperature is

122) According to the kinetic theory of gases, total energy of a gas is equal to

123) The average kinetic energy of a gas molecule can be determined by knowing

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

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

126) 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

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

128) The kinetic energy per gm mol for a diatomic gas at room temperature is

129) The translatory kinetic energy of a gas per gm is

130) 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

131) The translational kinetic energy of gas molecule for one mole of the gas is equal to

132) At 0 K which of the following properties of a gas will be zero

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

134) On absolute temperature, the kinetic energy of the molecules

135) On colliding in a closed container the gas molecules

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

137) The molecules of an ideal gas at a certain temperature have

138) Mean kinetic energy per degree of freedom of gas molecules is

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

140) An ideal gas is filled in a vessel, then

141) 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

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

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

144) 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

145) 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

146) 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

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

148) 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

149) 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

150) 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

151) Which one the following graphs represents the behaviour of an ideal gas

152) 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.

153) 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.

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

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

156) A diatomic molecule has how many degrees of freedom

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

158) 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

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

160) 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

161) In the absence of intermolecular forces of attraction, the observed pressure p will be

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

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

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

165) The specific heat of an ideal gas is

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

167) A monoatomic gas molecule has

168) The vapour of a substance behaves as a gas

169) The molecular weight of a gas is 44. The volume occupied by 2.2 g of this gas at 0â„ƒ and 2 atm. pressure will be

170) The temperature of a gas is -68â„ƒ. At what temperature will the average kinetic energy of its molecules be twice that of at -68â„ƒ?

171) A vertical column 50 cm long at 50â„ƒ balances another column of liquid 60 cm long at 100â„ƒ. The coefficient of absolute expansion of the liquid is

172) 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

173) The translational kinetic energy of gas molecule for one mole of the gas is equal to

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

175) If temperature of gas increases from 27â„ƒ to 927â„ƒ the K.E. will be

176) For an ideal gas

177) 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

178) The r.m.s. speed of gas molecules is given by

179) 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

180) 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

181) The amount of heat required to convert 10 g of ice at -10â„ƒ into steam at 100â„ƒ is (in calories)

182) The absolute temperature of a gas is determined by

183) 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

184) 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

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

186) A polyatomic gas with n degrees of freedom has a mean energy per molecule given by (N is Avogadroâ€™s number)

187) Two spheres made of same substance have diameters in the ratio1âˆ¶2. Their thermal capacities are in the ratio of

188) Volume of gas becomes four times if

189) 22 g of carbon dioxide at 27â„ƒ is mixed in a closed container with 16 g of oxygen at 37â„ƒ. If both gases are considered as ideal gases, then the temperature of the mixture is

190) 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

191) 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

192) 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

193) At 0 K which of the following properties of a gas will be zero

194) For ideal gas, which statement is not true

195) Under constant temperature, graph between P and 1/V is

196) 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

197) On 0â„ƒ pressure measured by barometer is 760 mm. What will be pressure at 100â„ƒ

198) KE per unit volume is E. The pressure exerted by the gas is given by

199) 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

200) Boyleâ€™s law holds for an ideal gas during

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

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

203) 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

204) The temperature of a gas contained in a closed vessel of constant volume increases by 1â„ƒ when the pressure of the gas is increased by 1%. The initial temperature of the gas is

205) In Boyleâ€™s law what remains constant

206) The degrees of freedom of a molecule of a triatomic gas are

207) 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

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

209) Air is filled in a bottle at atmospheric pressure and it is corked at 35â„ƒ. 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

210) The kinetic energy of translation of 20 g of oxygen at 47â„ƒ is (molecular wt. of oxygen is 32 g/mol and R = 8.3J/mol/K)

211) If a Vander-Waalâ€™s gas expands freely, then final temperature is

212) To what temperature should the hydrogen at room temperature (27â„ƒ) be heated at constant pressure so that the R.M.S. velocity of its molecules becomes double of its previous value

213) The temperature of the hydrogen at which the average speed of its molecules is equal to that of oxygen molecules at a temperature of 31â„ƒ, is

214) The pressure is exerted by the gas on the walls of the container because

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

216) 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

217) In thermal equilibrium, the average velocity of gas molecules is

218) The heat capacity per mole of water is (R is universal gas constant)

219) 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

220) 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

221) Molecules of a gas behave like

222) For an ideal gas of diatomic molecules

223) Oxygen boils at (-183â„ƒ). The temperature on the Fahrenheit scale is

224) Which one of the following graphs represents the behaviour of an ideal gas?

225) A gas at 27â„ƒ 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

226) S.I. unit of universal gas constant is

227) 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

228) 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

229) 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

230) A sample of gas is at 0â„ƒ. To what temperature it must be raised in order to double the r.m.s. speed of the molecule

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

232) When the temperature of a gas is raised from 27â„ƒ to 90â„ƒ, the percentage increase in the r.m.s. velocity of the molecules will be

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

234) 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

235) For a gas, the r.m.s. speed at 800 K is

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

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

238) 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

239) The molar specific heat at constant pressure for a monoatomic gas is

240) The ratio of mean kinetic energy of hydrogen and oxygen at a given temperature is

241) 310 J of heat is required to raise the temperature of 2 mole of an ideal gas at constant pressure from 25Â°C to 35Â°C. The amount of heat required to raise the temperature of the gas through the same range at constant volume is

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

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

244) 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

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

246) Volume-temperature graph at atmospheric pressure for a monoatomic gas (V in mÂ³,T in â„ƒ) is

247) 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

248) The average momentum of a molecule in an ideal gas depends on

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

250) 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

251) At what temperature the molecule of nitrogen will have same rms velocity as the molecule of oxygen at 127â„ƒ ?

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

253) A body takes 10 min to cool from 60â„ƒ to 50â„ƒ. If the temperature of surroundings is 25â„ƒ and 527â„ƒ respectively. The ratio of energy radiated by P and Q is

254) Kinetic theory of gases provide a base for

255) The temperature of an ideal gas is increased from 27â„ƒ to 927â„ƒ. The root mean square speed of its molecules becomes

256) The volume of a gas at 20â„ƒ is 200 ml. If the temperature is reduced to -20â„ƒ at constant pressure, its volume will be

257) The temperature of an ideal gas is reduced from 927â„ƒ to 27â„ƒ. The r.m.s. velocity of the molecules becomes

258) According to the kinetic theory of gases, the temperature of a gas is a measure of average

259) The tyre of a motor car contains air at 15â„ƒ . If the temperature increases to 35â„ƒ , the approximate percentage increase is (ignore to expansion of tyre)

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

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

262) What is the ratio of specific heats of constant pressure and constant volume for NH3

263) Which one of the following graph is correct at constant pressure

264) The average kinetic energy of a gas molecule can be determined by knowing

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

266) The product of the pressure and volume of an ideal gas is

267) 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

268) Two spheres made of same material have radii in the ratio1âˆ¶2. Both are at same temperature. Ratio of heat radiation energy emitted per second by them is

269) 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 31â„ƒ and 76 cm of mercury. If the air column at one end is kept at 0â„ƒ and the other end at 273â„ƒ , the pressure of air which is at 0â„ƒ is (in cm of Hg)

270) The relationship between pressure and the density of a gas expressed by Boyleâ€™s law, P=KD holds true

271) 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

272) 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

273) 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

274) An ideal gas is filled in a vessel, then

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

276) At what temperature is the root mean square velocity of gaseous hydrogen molecules equal to that of oxygen molecules at 47â„ƒ

277) At what temperature the kinetic energy of gas molecule is half of the value at 27â„ƒ?

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

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

280) If mass of He is 4 times that of hydrogen, then mean velocity of He is

281) At what temperature rms speed of air molecules is doubled of that at NTP?

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

283) Which of the following formula is wrong

284) If the mean free path of atoms is doubled then the pressure of gas will become

285) The specific heat of a gas

286) 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

287) For a real gas (van der Waalâ€™s gas)

288) Graph of specific heat at constant volume for a monoatomic gas is

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

290) The root mean square speed of the molecules of a gas is

291) At constant pressure, which of the following is true?

292) 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

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

294) A perfect gas at 27â„ƒ is heated at constant pressure to 327â„ƒ. If original volume of gas at 27â„ƒ is V then volume at 327â„ƒ is

295) Universal gas constant is

296) Which of the following statements about kinetic theory of gases is wrong

297) At constant pressure, the ratio of increase in volume of an ideal gas per degree rise in kelvin temperature to itâ€™s original volume is (T= absolute temperature of the gas)

298) The temperature of a given mass is increased from 27â„ƒ to 327â„ƒ . The rms velocity of the molecules increases

299) Mean kinetic energy per degree of freedom of gas molecules is

300) The specific heat relation for ideal gas is

301) A gas at 27â„ƒ 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

302) 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= boltzmannâ€™s constant]

303) 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 27â„ƒ. The pressure exerted by the mixture is

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

305) 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

306) 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

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

308) What is an ideal gas?

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

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

311) The average kinetic energy of a gas molecules is

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

313) If mass of He atom is 4 times that of hydrogen then mean velocity of He is

314) 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

315) A gas is collected over the water at 25â„ƒ. The total pressure of moist gas was 735 mm of mercury. If the aqueous vapour pressure at 25â„ƒ is23.8 mm. Then the pressure of dry gas is

316) 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

317) The kinetic energy per gmol for a diatomic gas at room temperature is

318) 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

319) The rate of diffusion is

320) r.m.s. velocity of nitrogen molecules at NTP is

321) Mean free path of a gas molecule is

322) 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

323) According to Maxwellâ€™s law of distribution of velocities of molecules, the most probable velocity is

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

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

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

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

328) According to the kinetic theory of gases, at absolute temperature

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

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

331) The relation between two specific heats of a gas is

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