The mean free path () of a gas sample is given by:
1.
2.
3.
4. none of these
Boyle's law is applicable in :
1. Isobaric process
2. Isochoric process
3. Isothermal process
4. Adiabatic process
Air at sea level is dense. This is a practical application of:
1. Boyle's law
2. Charles' law
3. Avogadro's law
4. Dalton's law
The condition of SATP refers to:
1. 25 C and 2 atm
2. 25 C and 1 atm
3. 0 C and 2 atm
4. 25 C and 1 bar
At what temperature will the total K.E. of 0.3 mol of He be the same as the total K.E. of 0.4 mol of Ar at 400 K
1. 400K
2. 300K
3. 346K
4. 533K
Rate of diffusion of LPG (a mixture of n-butane and propane) is 1.25 times of SO3. Hence, mass fraction of n-butane in LPG is
1. 0.75
2. 0.25
3. 0.50
4. 0.67
A spherical balloon of 21 cm dimeter is to be filled up with H2 at NTP from a cylinder containing the gas at 20 atm at 27o The cylinder can hold 2.82 litre of water at NTP. Calculate the number of balloons that can be filled up.
a) 20
b) 10
c) 15
d) 60
A 20 g chunk of dry ice is placed in an empty 0.75 litre bottle and tightly closed. The final pressure in the bottle after all CO2 has been evaporated and temperature reaches to 25oC is-
1. 20.6 atm
2. 12.6 atm
3. 15.8 atm
4. 2.8 atm
A 40 mL of a mixture of H2 and O2 was placed in a gas burette at 18 oC and 1 atm pressure. A spark was supplied so that the formation of water was complete . The remaining pure gas had a volume of 10 mL at 18 oC and 1 atm pressure. If the remaining gas was H2 , what was the initial mole percentage of H2 in the mixture?
1. 25%
2. 50%
3. 35%
4. 75%
60 mL of a mixture of equal volume of Cl2 and an oxide of chlorine was heated and then cooled back to the original temperature. The resulting gas mixture was found to have volume of 75 ml. On treatment with caustic soda solution, the volume contracted to 15 ml. Assume that all the measurements are made at same T and P. Deduce the simplest formula for oxide of Cl2. The oxide of Cl2 on heating decomposes quantitatively to O2 and Cl2.
(1) ClO
(2) Cl2O
(3) ClO4
(4) Cl2O3
For the reaction, N2 O5 (g)→2NO2 (g) + 0.5 O2 (g),
Calculate the mole fraction of N2 O5 (g) decomposed at a constant volume and temperature if the initial pressure is 600 mm Hg and the pressure at any time is 960 mm Hg. Assume ideal gas behaviour.
(1) 0.4
(2) 0.2
(3) 0.1
(4) 0.5
If density of vapours of a substance of molar mass 18 g/mole at 1 atm pressure and 500 K is
0.36 kg m–3 , then the value of Z for the vapours is-
(R = 0.082 L atm mole K–1)
1.
2.
3. 1.1
4. 0.9
Equal amount (mass) of methane and ethane have their total translational kinetic energy in the ratio
3: 1 then their temperatures are in the ratio.
(1) 5 : 8
(2) 45 : 8
(3) 15 : 8
(4) 8 : 5
The graph that represents an isobar is-
1.
2.
3.
4.
A sample of water gas has a composition by volume of 50% H2, 45% CO and 5% CO2. Calculate the volume in litre at S.T.P. of water gas which on treatment with excess of stream will produce 5 litre H2. The equation for the reaction is : CO + H2O CO2+ H2
(1) 4.263 Litre
(2) 5.263 Litre
(3) 6.263 Litre
(4) 7.263 Litre
Flask A of volume 10 litre containing 20 gram of H2 and flask B of volume 10 litre containing 88 gram CO2 are connected by a connector having negligible volume. When the valve of the connector is opened, the composition of H2 gas in flask B after opening the valve is-
1. 10%
2. 13%
3. 15%
4. 20%
A mixture of two gases A and B in the mole ratio 2 : 3 is kept in a 2 litre vessel. A second 3 litre vessel has the same two gases in the mole ratio 3 : 5. Both gas mixtures have the same temperature and same total pressure. They are allowed to intermix ,the final temperature and total pressure are the same as the initial values, the final volume being 5 litres. Given that the molar masses are MA and MB, what is the mean molar mass of the final mixture?
(1)
(2)
(3)
(4)
At a certain temperature for which RT = 25 lit. atm. mol–1, the density of a gas, in gm lit–1, is d = 2.00P + 0.020 P2, where P is the pressure in atmosphere. The molecular weight of the gas in gm mol–1 is-
1. 25
2. 50
3. 75
4. 100
Themolecular radius for a certain gas = 1.25 A. What is a reasonable estimate of the magnitude of the van der Wails constant, b, for the gas?
(1) 0.98 × 10–2 litre/mole
(2) 1.43 × 10–2 litre/mole
(3) 1.97 × 10–2 litre/mole
(4) 3.33 × 10–2 litre/mole
A sample of a given mass of a gas at a constant temperature occupies 95cm3 under a pressure of . At the same temperature, the volume at a pressure of is [Bihar CEE 1992]
1. 190 cm3
2. 93 cm3
3. 46.5 cm3
4. 47.5 cm3
When the temperature of 23 ml of dry CO2 gas is increased from 10° to 30°C at a constant pressure of 760 mm, the volume of gas becomes-
1. 7.7 ml
2. 25.5 ml
3. 24.6 ml
4. 69 ml