# The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from a volume of $10 \; dm^3$ to a volume of $100\; dm^3$ at $27^ {\circ} C$ is :
( A ) $32.3\; J\;mol^{-1}K^{-1}$
( B ) $38.3\; J\;mol^{-1}K^{-1}$
( C ) $42.3\; J\;mol^{-1}K^{-1}$
( D ) $35.8\; J\;mol^{-1}K^{-1}$