Internal Energy

IMPORTANT

Internal Energy: Overview

This topic covers concepts, such as, Internal Energy, Characteristics of Internal Energy, Thermodynamical Interpretation of Ideal Gas, Change in Internal Energy for Ideal Gas & Law of Equipartition of Energy etc.

Important Questions on Internal Energy

EASY
IMPORTANT

Internal energy and pressure of a gas per unit volume are related as:

HARD
IMPORTANT

A container is filled with 20 moles of an ideal diatomic gas at absolute temperature T. When heat is supplied to gas temperature remains constant but 8 moles dissociates into atoms. Heat energy supplied to gas is?

MEDIUM
IMPORTANT

Which amongst the following options is the correct relation between change in enthalpy and change in internal energy?

MEDIUM
IMPORTANT

1672 cal of heat is given to one mole of oxygen at 0°C keeping the volume constant. Raise in temperature is (Cp=7 cal g-1K-1 and R=2cal mol-1K-1)

MEDIUM
IMPORTANT

According to law of equipartition of energy, the average energy associated with each degree of freedom is:

MEDIUM
IMPORTANT

The process in which the value of U = 0 is:

HARD
IMPORTANT

A thermally insulated rigid container of 1 L volume contains a diatomic ideal gas at room temperature. A small paddle installed inside the container is rotated from the outside, such that the pressure rises by 105 Pa. The change in internal energy is close to

HARD
IMPORTANT

The internal energy (U) of an ideal gas is plotted against volume for a cyclic process ABCDA, as shown in the figure.

Question Image

The temperature of the gas at B and C are 500 K and 300 K, respectively. The heat absorbed by the gas (in cal/mol) in this cyclic process, is :

EASY
IMPORTANT

How much heat will be required at constant volume at 727°C to form 1.28 kg of CaC2 from CaO(s) and C(s)

Given: ΔfH(CaO,s)=152kcal/mol

ΔfHCaC2,s=14kcal/mol

ΔfH(CO,g)=24kcal/mol

EASY
IMPORTANT

one mole of an ideal gas at 300 K is expanded isothermally from an initial volume of 1  litre to 10 litre. The ΔU for this process is: R=2 cal K-1 mol-1

EASY
IMPORTANT

An ideal gas initially at temperature T1 with γ=5/3 expands adiabatically into vacuum to double its volume. The final temperature T2 is given by:

EASY
IMPORTANT

A diatomic ideal gas changes its state from A to B as shown in the figure.

Question Image

Choose the correct U versus V graph: (where U is internal energy of the gas)

HARD
IMPORTANT

Which of the following statement is INCORRECT ?

EASY
IMPORTANT

The internal energy of an ideal gas increases during an isothermal process when the gas is :-

MEDIUM
IMPORTANT

200 J of heat is provided to the system. Work done on the system is 20 J. What is the change in internal energy?
 

MEDIUM
IMPORTANT

One mole of an ideal gas at 300 K is expanded isothermally from an initial volume of 1 Litres to 10 litres. The U for this process is (R= 2 cal mol-1 K-1)

HARD
IMPORTANT

In the reaction, H2(g)+Cl2(g)2HCl(g) ΔH=-184kJ if 2 moles of H2 react with 2 moles of Cl2, then U is equal to

MEDIUM
IMPORTANT

A gas does 0.320 kJ of work on its surroundings and absorbs 120 J of heat from the surroundings. Hence, U is 

EASY
IMPORTANT

When a sample of an ideal gas is allowed to expand at constant temperature against an atmospheric pressure,

EASY
IMPORTANT

To break one bond in DNA, the amount of energy to be supplied is 0.06 eV. The value of this energy in joules is approximately;