States of Matter

A bubble of air is underwater at temperature 15 and the pressure 1.5 bar. If the bubble rises to the surface where the temperature is 25 and the pressure is 1.0 bar, what will happen to the volume of the bubble?

1. Volume will become greater by a factor of 1.6.
2. Volume will become greater by a factor of 1.1.
3. Volume will become smaller by a factor of 0.70.
4. Volume will become greater by a factor of 2.5.

By what factor does the average velocity of a gaseous molecule increase when the temperature (in Kelvin) is doubled?

1. 2.0
2. 2.8
3. 4.0
4. 1.4

Two gases A and B having the same volume diffuse through a porous partition in 20 and 10 seconds respectively. The molecular mass of A is 49 u. Molecular mass of B will be

1. 50.00 u
2. 12.25 u
3. 6.50 u
4. 25.00 u

A gaseous mixture was prepared by taking equal moles of CO and N2. If the total pressure of the mixture was found to be 1 atmosphere, the partial pressure of the nitrogen (N2) in the mixture is

1. 0.5 atm
2. 0.8 atm
3. 0.9 atm
4. 1 atm

The pressure exerted by 6.0 g of methane gas in a 0.03 m3 vessel at 129 is (Atomic masses : C = 12.01, H = 1.01 and R = 8.314 J K-1 mol-1)

1. 215216 Pa
2. 13409 Pa
3. 41648 Pa
4. 31684 Pa

If a gas expands at constant temperature, it indicates that

1. kinetic energy of molecules remains the same
2. number of the molecules of gas increases
3. kinetic energy of molecules decreases
4. pressure of the gas increases

The surface tension of which of the following liquids is maximum ?

1. C2H5OH
2. CH3OH
3. H2O
4. C6H6

Van der Waals real gas acts as an ideal gas at which conditions?

1. High temperature, low pressure
2. Low temperature, high pressure
3. High temperature, high pressure
4. Low temperature, low pressure

The beans are cooked earlier in pressure cooker because

1. boiling point increases with increasing pressure
2. boiling point decreases with increasing pressure
3. extra pressure of pressure cooker softens the beans
4. internal energy is not lost while cooking in pressure cooker

Which of the following expressions correctly represents the relationship between the average molar kinetic energy, KE, of CO and N2 molecules at the same temperature?

1. KECO = KEN2
2. KECO > KEN2
3. KECO < KEN2
4. cannot be predicted unless volumes of the gases are given