• # question_answer 64) For the reaction, ${{C}_{3}}{{H}_{8}}(g)+5{{O}_{2}}\xrightarrow{{}}3C{{O}_{2}}(g)+4{{H}_{2}}O(l)$ at constant temperature, $\Delta H -\Delta U$ is A) $+RT$B) $-3RT$C) $+3RT$D) $-RT$

$\Delta H=\Delta U+\Delta nRT$$\because$$\Delta n=3-5-1=-3$ $\therefore$ $\Delta H-\Delta U=-3RT$