Question
An ideal gas $$A$$ and a real gas $$B$$ have their volumes increased from $$V$$ to $$2V$$ under isothermal conditions. The increase in internal energy
A.
will be same in both $$A$$ and $$B$$
B.
will be zero in both the gases
C.
of $$B$$ will be more than that of $$A$$
D.
of $$A$$ will be more than that of $$B$$
Answer :
will be zero in both the gases
Solution :
A change in pressure and volume of a gas without any change in its temperature is called an isothermal change. In such a change, there is a free exchange of heat between the gas and its surroundings.
$$\therefore T = {\text{constant,}}\,\,\Delta T = 0$$
So, internal energy $$\left( U \right)$$ remains constant is $$\left( {\Delta U = 0} \right).$$