If the pressure of a given mass of gas is reduced to half and temperature is doubled simultaneously, the volume will be

The molecules of a gas A travel four times faster than the molecules of gas B at same temperature. The ratio of molecular weights (M_A/M_B) is

The ratio of rms velocity to average velocity of gas molecule at a particular temperature is

X ml of H₂ gas effuses through a hole in a container in 5 secs. The time taken for effusion of same volume of gas specified below under identical condition is

(a) 10 secs : He                           (b) 20 secs : O₂

(c) 25 secs : CO                           (d) 55 secs : CO₂

The compressibility factor for an ideal gas is

On increasing temperature, the fraction of total gas molecule which has acquired most probable velocity will

Which of the following pair will diffuse at the same rate?

(a) CO₂ and N₂O            (b) CO₂ and NO            

(c) CO₂ and CO              (d) N₂­O and NO

The value of Vander Waals constant ‘a’ is maximum for

(a) Helium             (b) Nitrogen            (c) CH₄             (d) NH₃

A mixture of H₂ and O₂ in 2 : 1 volume is allowed to diffuse through a porous partition. What is the composition of gas coming out initially?

With increasing temperature of gas

Mean free path of a gas is ‘ℓ’ cm. Which of the following relation is true? [T is temperature in K and P is pressure]

(a) ℓ µ √T                 (b) ℓ µ T^3/2              (c) ℓ µ p                  (d) ℓ µ 1/p

At temperature 298 K one mole of a real gas has volume 18.5 lit at 1.2 atm. pressure. Another real gas has volume 14.9 lit mol^-1 at 278 Kand 1.5 atm pressure. Then

The compressibility factor of a Vander Waal’s gas is

(a)                  (b)                       (c)                       (d) None of these

NH₃ is liquefied more easily than N₂. Hence

(a) a and b of NH₃ is greater than that of N₂

(b) a(NH₃) > a(N₂) but b(NH₃) < b(N₂)

(c) a(NH₃) < a(N₂) but b(NH₃) > b(N₂)

(d) None

2 mole sample of hydrocarbon C_xH_y yields after complete combustion with excess O₂ gas, 0.8 mole of CO₂, 1.1 mole of H₂O. Hence hydrocarbon is

(a) C₄H₁₀           (b) C₄H₈             (c) C₄H₅             (d) C₈H₁₆

Volume of the air that will be expelled from a vessel of 300 cm³ when it is heated from 27^oC to 37^oC at the same pressure will be

(A) 310 cm³                        (B) 290 cm³                  (C) 10 cm³                 (D) 37 cm³

A sealed tube which can withstand a pressure of 3 atmosphere is filled with air at 27^oC and 760 mm pressure. The temperature above which the tube will burst will be

(A) 900^oC                          (B) 627^oC                         (C) 627^oC                       (D) 1173^oC

400 cm³ of oxygen at 27^oC were cooled to –3^oC without change in pressure. The contraction in volume will be

(A) 40 cm³                        (B) 30 cm³                         (C) 44.4 cm³                          (D) 360 cm³

A gas occupied a volume of 250 ml at 700 mm Hg pressure and 25^oC. What additional pressure is required to reduce the gas volume to its 4/5^th value at the same temperature?

At constant temperature, if pressure increases by 1% the percentage decreases of volume is

Two glass bulbs A and B are connected by very small tube having a stop cock. Bulb A has a volume of 100 ml and contained the gas while bulb B was empty and had a volume of 150 ml. On opening the stop cock, the pressure of the gas in bulb A will fall down to

The density of a gas at 27^oC and 1 atm is d pressure remaining constant at which of the following temperature will its density become 0.75 d?

(A) 20^oC                           (B) 30^oC                           (C) 400 K                        (D) 300 K

At 0^oC and one atm pressure, a gas occupies 100 cc. If the pressure is increased to one and a half-time and temperature is increased by one third of absolute temperature, then final volume of the given will be

Pressure of a mixture of 4g of O₂ and 2g of H₂ confined in a bulb of 1 litre at 0^oC is

2 g of gaseous substance A is introduced into an evacuated flask at 25°.The pressure is 1 atm. 3 g of gas B is introduced along with A and the pressure increases by 0.5 atm. The ratio of molecular weights is :

When equal weights of O₂ and N₂ are placed in separate containers of equal volume at the same temperature, which of the following statement is true?

An under water bubble present at the bottom of the tank having radius 0.5 cm where T is 7^oC and P is 7 atm rises to the surface, where T is 47^oC and P is 1 atm. What will be the radius of bubble at the surface?

A sample of a given mass of a gas at a constant temperature occupied 95 cm³ under a pressure of 9.962×10⁴ Nm^-2. At the same temperature its volume at a pressure of 10.13×10⁴ Nm^-2 is

A gas in an open container is heated from 27°C to 127°C. The fraction of the original amount of gas left in the container would be

The concentration of gas in a container is 0.1 mol L^–1. What is the pressure of gas at 273°C

In a container x g of a gas is placed. After some time some gas is allowed to escape from container. The pressure of gas becomes half and absolute temperature 2/3^rd. The amount of gas escaped is

1L of a gas weighs 2g at 300K and 1 atm pressure. If the pressure is reduced to 0.75 atm, at which of the following temperature will 1L of the same gas weigh 1g?

(A) 800 K                         (B) 450 K                      (C) 177°C                         (D) 450°C  

Equal weight of ethane and hydrogen are mixed in an empty container at 25°C. The fraction of total pressure exerted by hydrogen is

Two separate bulbs containing ideal gas A & B are taken. Density of A is twice that of B. Molecular weight of A is half that of B. If the two gases are at the same temperature, the ratio of the pressure of A to that of B is?

Under which of the following two conditions percentage increase in volume of a gas will be more
i)    On increasing temp. from 100°C to 110°C, P is kept constant
ii)   On increasing temp from 100 K to 110 K, keeping pressure constant

2 gm of H₂ and 17 gm NH₃ are placed in a 8.21 litre flask at 27°C. The total pressure of the gas mixture is

The density of Neon is maximum at

(A) STP                                                          (B) 0°C, 2atm
(C) 273°C, 1 atm                                          (D) 273°C, 2 atm

Two non reacting gases G₁ (of molar mass M₁) and G₂ (of molar mass M₂) were taken in their weight ratio 2:3 in a closed container. If the pressure of the gas G₁ was just double of the pressure of the gas G₂ in the mixture. Then M₁/M₂ will be

Under which of the following conditions the density of a gas will remain unchanged?

An open vessel contains 200 mg of air at 17°C. What weight percent of air would be expelled if the vessel is heated to 117°C

Which of the following quantities is the same for all ideal gases at the same temperature?

A sample of O₂ gas is collected over water at 23^oC at a barometric pressure of 751 mm Hg (vapour pressure of water at 23^oC is 21mm Hg). The partial pressure of O₂ gas in the sample collected is

Same mass of CH₄ and H₂ is taken in container. The partial pressure caused by H₂ is, with respect to total pressure

160 ml of a gas are collected over water at 25^oC and 745 mm Hg. If aqueous tension at 25^oC is 23.8 mm Hg, then pressure of dry gas at 25^oC is :

In a flask of volume V litres, 0.2 mol of oxygen, 0.4 mol of nitrogen, 0.1 mol of ammonia and 0.3 mol of helium are enclosed at 27^oC. If the total pressure exerted by these non-reacting gases is one atmosphere, the partial pressure exerted by nitrogen is

The volume of 0.0168 mol of O₂ obtained by decomposition of KClO₃ and collected by displacement of water is 428 ml at a pressure of 754 mm Hg at 25^oC. The pressure of water vapour at 25^oC is

Dalton’s law of partial pressure will not hold good for which of the following mixture

(A) H₂ + O₂ + CO₂                                             (B) N₂ + HBr + Cl₂

(C) Cl₂ + HBr + NH₃                                                  (D) NH₃ + O₂ + Cl₂

If the pressure is halved and absolute temperature doubled, the volume of the gas will be

An equimolar mixture of O₂,N₂ and He contained in a closed vessel exerts a pressure  of 900 m.m. If half of the total molecules of N₂ be removed from the vessel final pressure will be

1 litre CO and 1.75 litre CH₄ at the same temp and pressure were mixed together. What is the relation between the masses of two gases in the mixture

(A)                                     (B) 

(C)                                  (D) 

The time taken for a certain volume of a gas ‘X’ to diffuse through a small hole is 2 minutes. It takes 5.65 minutes for oxygen to diffuse under the similar conditions. The molecular weight of ‘X’ is

At what temperature, the rate of effusion of N₂ would be 1.625 times that of SO₂ at 50^oC ?

50 volumes of H₂ takes 25 minutes to diffuse out of vessel. How long will 40 volumes of oxygen take to diffuse out from the same vessel under similar conditions ?

If the four tubes of a car are filled to the same pressure with N₂, O₂, H₂ and Ne separately, then which one will be filled first ?

(A) N₂                           (B) O_­2                                (C) H₂                      (D) Ne

A balloon filled with ethyne is pricked with a sharp point and quickly dropped in a tank of H₂ gas under identical conditions. After a while the balloon will have

The rate of diffusion of methane at a given temperature is twice that of a gas X. Molecular weight of X is

A mixture of SO₂ and He gases in 4:1 molar proportions is allowed to effuse through a small orifice. The ratio of number of moles of SO₂ and He in the initially effused gas mixture will be

The volumes of a gas X and Cl₂ diffusing through a plug at the same time are 35 ml and 29 ml respectively. If the molecular mass of Cl₂ is 71, the molecular mass of X is

A balloon filled with N₂O is pricked with a sharper point and plunged into a tank of SO₂ under the same pressure and temperature. The balloon will

50 ml of a gas A diffuse through a membrane in the same time as for the diffuse of 40 ml of a gas B under identical temperature and pressure conditions. If mol weight of A is 64, what is that of B

Under identical experimental condition which of the following pair of gas will be most easy to separate by diffusion process?

(A) H₂ and D₂                                                     (B) U²³⁵F₆ and U²³⁸F₆

(C) CO₂ and C₃H₈                                              (D) O₂ and N₂

Under same condition of temp. and pressure, a cycloalkene was found to diffuse 3√3  times slower than hydrogen. Cycloalkene is

At what temperature will the average speed of CH₄ molecules have the same values as O₂ has at 300 K ?

The kinetic energy for 14 grams of nitrogen gas at 127^oC is nearly (mol. Mass of nitrogen = 28 and gas constant = 8.31 JK^–1 mol^–1)

By how many folds the temperature of a gas would increase when the r.m.s. velocity of gas molecules in a closed container of fixed volume is increased from 5 x 10⁴ cm s^–1 to 10 x 10⁴ cm s^–1

The total kinetic energy of a sample of gas which contains N molecules at –123^oC is E_k joules. Another sample of gas at 27^oC has total kinetic energy 2 E_k joules. The number of molecules in the second sample of gas is:

Absolute zero is defined as the temperature

In deriving the kinetic gas equation, use is made of the root mean square velocity of the molecules because it is

The average velocity of an ideal gas molecule at 27°C is 0.3 m/sec. The average velocity at 927°C will be

The ratio between the root mean square velocity of H₂ at 50 K and that of O₂ at 800 K is

The r.m.s. velocity of hydrogen is √7  times the r.m.s velocity of nitrogen if T is the temperature of the gas

(A) T(H₂) = T(N₂)                                                (B) T(H₂) > T(N₂)
(C) T(H₂) < T(N₂)                                                (D) T(H₂) = √7 T(N₂)

The average K.E per mole of an ideal gas at 27°C is

(A) 3.74 KJ                                           (B) 3.695 KJ

(C) 984.15 KJ                                      (D) 3.7 × 10¹⁰ KJ

At what temperature will the total K.E. of 0.5 mole of He be the same as the total K.E. of 0.6 mole of Ne at 300 K ?

At constant pressure, the change in rms velocity (Vmrs) of an ideal gas depends on the density of the gas as

(A) d²                      (B) d                          (C) √d                         (D) 1/√d

Average KE of CO­₂ gas at 27°C is E. what will be the average KE of N₂ molecules at the same temperature.

In a given sample of gas, molecules move with velocities 20m/s, 30 m/s and 40 m/s. Its root mean square velocity will be

Boltzmann constant (k) is given by

(A) k = R × N_A                                          (B) k = R/N_A

(C) k = N_A/R                                            (D) k = 1.387 × 10^-4 KJ^-1

At high temperature and low pressure, the van der Waals equation is reduced to

(A)
(B) pV_m = RT
(C) p(V_m – b) = RT
(D) 

In the corrections made to the ideal gas equation for real gases, the reduction in pressure due to attractive forces is directly proportional to

(A) n / V                          (B) nb                       (C) n²/V²b                        (D) n²/V²

Generally, greater the value of the van der Waals constant b of a gas, the greater is the size of the molecule. Which of the following is an exception to this rule?

The compressibility factor for a gas under a given set of conditions is found to be equal to 0.989. The gas under the given set of condition is

At very low pressure the vander Waal’s equation reduces to

(A) PV = RT – a/ V                                        (B) PV = (RT)^–1

(C) PV = RT                                                  (D) PV = RT + Pb

Gases deviate from ideal behaviour because their molecules

If 8 g methane be placed in 5 Lt container at 27°C. Its Boyle’s constant will be

However great the pressure, a gas cannot be liquefied above its

The Vander Waals constant ‘a’ for the gases O₂, N₂, NH₃ and CH₄ are 1.3, 1.390, 4.170 and 2.253 L² atm mol^-2 respectively. The gas which can be most easily liquefied is

(A) O₂                         (B) N₂                         (C) NH₃                      (D) CH₄

Temperature at which a real gas obeys the ideal gas laws over fairly wide range of pressure is referred to as

A 0.20 mol sample of a hydrocarbon C_xH_y yields after complete combustion with excess O₂ gas, 0.80 mol of CO₂ and 1.0 mol of H₂O. Hence hydrocarbon is

(A) C₄H₁₀                       (B) C₄H₈                               (C) C₄H₆                         (D) C₈H₁₆

Under identical condition of temperature and pressure one litre of CH₄ weighed 1.2 gm while 2 litre of another gaseous hydrocarbon C_nH_2n–2 weighed 8.1 gm. Value of n will be

A volume V of a gas at a temperature T₁ and a pressure p is enclosed in a sphere. It is connected to another sphere of volume V/2 by a tube and stopcock. The second sphere is initially evacuated and the stopcock is closed. If the stopcock is opened the temperature of the gas in the second sphere becomes T₂. The first sphere is maintained at a temperature T₁. What is the final pressure p₁ within the apparatus?

(A)                                                   (B) 

(C)                                                    (D) 

Which of the following are true statements ?

Which of the following is/are true?
(A) The van der Waal’s constant ‘a’ is the correction for pressure
(B) The van der Waal’s constant b is the actual volume of the gas molecule
(C) Units of ‘a’ are atm L² mol^–2
(D) Units of b are mol L^–1

Vander Waal’s constant ‘b’ of a gas is 125.57 centilitre/mole. How near can be the centres of the two molecules approach each other

(A) 5 x 10^-4 cm                                                  (B) 1.0 x 10^-7 cm
(C) 5 x 10^-8 cm                                                  (D) 1.0 x 10^-7 m

Which of the following equation(s) is / are incorrect  for 0.5 moles of real gas 

(A)                                        (B) 
(C)                                        (D)  PV = 0.5 RT

According to Charles’ law

(A) V = 1/T                         (B)                          (C)                    (D)