Question

For the reaction,
$C _{3} H _{8}( g )+5 O _{2}( g ) \longrightarrow 3 CO _{2}( g )+4 H _{2} O ( l )$
at constant temperature, $\Delta H-\Delta E$ is

• A. RT
• B. - 3RT
• C. 3RT
• D. - RT

Answer 1

Answer: (B)

$C _{3} H _{8}( g )+5 O _{2}( g ) \longrightarrow 3 CO _{2}( g )+4 H _{2} O ( l )$
$\Delta n_{g}=n_{p}-n_{r}$
$=3-6=-3$
$\Delta H=\Delta E+\Delta n_{g} R T$
$\Delta H=\Delta E-3 R T$
$\Delta H-\Delta E=-3 R T$