Question

For a certain reaction the change in enthalpy and change in entropy are $40.63\, kJ \,mol ^{-1}$ and $100\, JK ^{-1} .$ What is the value of $\Delta G$ at $27^{\circ} C$ and indicate whether the reaction is spontaneous or not-

• A. $+10630\, J \,mol ^{-1}$; spontaneous
• B. $+10630\, J \,mol ^{-1}$; non spontaneous
• C. $-7990 \,J \,mol ^{-1}$; spontaneous
• D. +7900 J mol $^{-1}$; spontaneous

Answer 1

Answer: (B)

$\Delta G=\Delta H-T \Delta S$, given

$T=27^{\circ} C =273+27=300$

$=40.63 \times 10^{3}-300 \times 100$

$=10630 \,J / mole ;$ non-spontaneous.