The heat absorbed during the isothermal expansion of an ideal gas against vacuum is zero.
The volume occupied by the molecules of an ideal gas is zero.

Options

A. If both (A) and (R ) are correct, and (R ) is the correct explanation for (A).
B. If the both (A) and (R ) are correct, but(R ) is not a correct explanation for (A).
C. If (A) is correct, but (R ) is incorrect.
D. If both (A) and (R ) are incorrect.

Explanation

The heat absorbed during the isothermal expansion of an ideal gas against vacuum is zero. This is because there are no forces of attraction between the gas molecules. The volume occupied by the molecules of an ideal gas is zero. For an ideal gas, they are point molecules.