# The molar heat capacity $\;(C_{p})\;$ of $\;CD_{2}O\;$ is 10 cals at 1000 K . The change in entropy associated with cooling of 32 of g of $\;CD_{2}O\;$ vapour from 1000 K to 100 K at constant pressure will be : (D=deuterium , at . mass = 2u)

$(a)\;23.03\;cal\;deg^{-1} \qquad(b)\;-23.03\;cal\;deg^{-1}\qquad(c)\;2.303\;cal\;deg^{-1}\qquad(d)\;-2.303\;cal\;deg^{-1}$