Behaviour of Real Gases

IMPORTANT

Behaviour of Real Gases: Overview

This Topic covers sub-topics such as Compressibility Factor, Real Gas, Boyle's Temperature, Deviations from Ideal Gas Behaviour, Van der Waals Equation for Real Gases, Compressibility of Gas and, Units of van der Waals Constants

Important Questions on Behaviour of Real Gases

HARD
IMPORTANT

The pressure exerted by 1 mole of CO2 at 273 K, is 34.98 atm. Assuming that volume occupied by CO2 molecules is negligible, the value of van der Waals' constant for attraction of CO2 gas is :

MEDIUM
IMPORTANT

A gas is said to behave like an ideal gas when relation PVT=constant. When do you expect real gas to behave like an ideal gas?

EASY
IMPORTANT

In Van der Waal’s equation of state for a non-ideal gas, the term that accounts for intermolecular forces is:

MEDIUM
IMPORTANT

Van der Waal’s real gas, act as an ideal gas, at which conditions ?

EASY
IMPORTANT

At which one of the following temperature – pressure conditions the deviation of a gas from ideal behaviour is expected to be minimum ?

EASY
IMPORTANT

When deviation is more in the behaviour of a gas from the ideal gas equation PV = nRT ?

EASY
IMPORTANT

According to kinetic theory, the gas particles occupy a negligible fraction of the total volume of the gas. This assumption is responsible for the volume correction in the ideal gas equation of real gases.

EASY
IMPORTANT

Mentions two assumptions of kinetic theory of gases, which are responsible for the volume correction in the ideal gas equation of real gases.

MEDIUM
IMPORTANT

Explain the factors responsible for the volume correction in the ideal gas equation of real gases.

HARD
IMPORTANT

The isotherms of a gas are shown below :

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Among the following,

(i) At T1, the gas cannot be liquefied

(ii) At point B, liquid starts to appear at T2

(ii) TC is the highest temperature at which the gas can be liquefied

(iv) At point A, a small increase in pressure condenses the whole system to a liquid

The correct statements are :

EASY
IMPORTANT

Which of the following expressions is correct between the van der Waals constant b and the radius r of spherical molecules?

EASY
IMPORTANT

For an ideal gas, the compressibility factor is

HARD
IMPORTANT

For one mole of a van der Waals' gas, the compressibility factor Z=pVRT at a fixed volume will certainly decrease, if
[Given : " a " and " b " are standard parameters for van der Waals' gas]
 

MEDIUM
IMPORTANT

The pressure p and volume V isotherm of a van der Waals' gas, at the temperature at which it undergoes gas to liquid transition, is correctly represented by

EASY
IMPORTANT

n2av2 is also called internal _____ of the gas where 'a' is a measure of force of attraction between gas molecule.

EASY
IMPORTANT

Which of the following represents a plot of compressibility factor Z vs pressure P at room temperature for O2?

MEDIUM
IMPORTANT

Under which of the following conditions does a gas deviate the most from ideal behaviour?

HARD
IMPORTANT

Write invalid Assumptions of Kinetic Theory for Real Gases which are questionable.

HARD
IMPORTANT

For real gases, as pressure increases, the volume of a gas becomes very small and approaches zero.

HARD
IMPORTANT

For one mole of a van der Waals gas when b=0 and T=300 K, the PV vs I/V plot is shown below. The value of the van der Waals constant 'a' (atm. litre2 mol-2) is
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