Test: Gaseous State - 6 - Chemistry MCQ

518 nm

1035 nm

 743 nm​

 325 nm

2.5R

R

1.5R

2R

The pressure exerted by the gas is proportional to the mean velocity of the molecule

The pressure exerted by the gas is proportional to the root mean square velocity of the molecule

The mean translational kinetic energy of the molecule is proportional to the absolute temperature

The root mean square velocity of the molecule is inversely proportional to the temperature

4

1

2

¼

1.5

2.0

1.0

∞

20 seconds: O₂

10 seconds: He

25 seconds: CO

55 seconds: CO₂

2.4 atm

1.2 atm

2 atm

1 atm

Cooling of the gas

Warming of the gas

No change in temperature

First cooling and then warming

P_ideal > P_real

V_ideal > V_real

P_ideal < P_real

V_ideal < V_real

3.0 m/s

0.3 m/s

0.9 m/s

0.6 m/s

II only

III only

II and III only

I , II, III

 at constant temperature

 at constant temperature

It is not possible to compress a gas at a temperature below T_C

At a temperature below T_C, the molecules are close enough for the attractive forces to act, and condensation occurs

No condensation takes place above T_C

Due to higher kinetic energy of the gas molecules above T_C, it is considered as super critical fluid

As the temperature is reduced, the volume as well as the pressure increase

As the temperature is reduced, the volume becomes zero and the pressure reaches infinity

As the temperature is reduced, the pressure decrease

A point is reached where, theoretically, the volume become zero

The effects of the repulsive and attractive intermolecular forces just offset each other

The repulsive intermolecular forces are greater than the attractive intermolecular forces

The repulsive intermolecular forces are less than the attractive intermolecular forces

The average translat ional K.E. per molecule is the same for N₂ and CO₂

The density of N₂ is less than that of CO₂

All of these

The total translational K.E. of both N₂ and CO₂ is the same

It is the highest temperature at which liquid and vapour can coexist

Beyond this temperature, there is no distinction between the two phases and a gas cannot be liquefied by compression.

At this temperature, the gas and the liquid phases have different critical densities

All are correct

As temperature increases, the peak (maxima) of a curve is shifted towards right side

As temperature increases, the most probable velocity of molecules increases but fraction of molecules of maximum velocity decreases

The area under the curve at all the temperature is the same because it represents the number of gaseous molecules

The fractions of molecules having different velocities at a given temperature

The temperature increases

The kinetic energy of the gaseous molecules remains same

The kinetic energy of gaseous molecules decreases

The number of molecules of the gas decrease

The product of pressure and volume of fixed amount of a gas is independent of temperature

The value of universal gas constant depends upon temperature, volume and number of gaseous molecules

The gas constant also know as Boltzmann’s constant

The average energy of molecules depends only on temperature

Total area under the two curves is independent of moles of gas

U_mps decreases as temperature decreases

T₁ > T₂ and hence higher the temperature, sharper the curve

The fraction of molecules having speed = U_mps decreases as temperature increases

At Boyle’s temperature a real gas behaves like an ideal gas at low pressure

Above critical conditions, a real gas behave like an ideal gas

For hydrogen gas ‘b’ dominates over ‘a’ at all temperature

At high pressure van der Waal’s constant ‘b’ dominates over ‘a’ 

The value of compressibility factor ‘Z’ for H₂ gas is greater than one at room temperature and pressure

The real gas behaves as an ideal gas a Boyle’s temperature

For a real gas following van der Waal’s equation of state, the expression of critical temperature is 

At low pressure, the compressibility factor  for a van der Waal’s gas.

In low pressure region repulsive forces dominates and high pressure region attractive forces dominates

Volume of gas particles is not negligible in low pressure region

Gases behaves as an ideal gas at low pressure and low temperature

All of the above

A real gas can be liquefied at critical temperature

Critical pressure is the maximum pressure at which substance present in its liquid state at T_C

Ideal gas can be liquefied below T_C

Critical volume is the molar volume or substance in gaseous state at T_C and P_C

At very low pressure real gases  show minimum deviation from ideal behaviour.

Real gas show maximum deviation at high pressure and low temperature

At Boyle temperature real gas behave as ideal gas in high pressure region

The compressibility factor for an ideal gas is zero

The volume increases

The mass of gas remains same

The kinetic energy of the molecules increases

Attraction forces between gas particles increases

We can condense vapour simply by applying pressure

To liquefy a gas one must lower the temperature below T_C and also apply pressure

At T_C, there is no distinction between, liquid and vapour state hence density of the liquid is nearly equal to density of the vapour

However great the pressure applied, a gas cannot be liquefied below it’s critical temperature.

Critical volume of A < Critical volume of B

Critical pressure A > Critical pressure of B

Critical temperature of A > Critical temperature of B

Critical temperature of A = Critical temperature of B