Question

Consider the values of $\Delta H^o$ (in $kJ{mol}^{-1}$) and for $\Delta S^o$ (in $J{mol}^{-1}{K}^{-1}$) given for four different reactions. For which reaction will $\Delta G^o$ increase the most positive) when temperature is increased from $0^{o}C$ to ${25}^{o}C$?

• A. $\Delta H^o=50,\Delta S^o=50$
• B. $\Delta H^o=90,\Delta S^o=20$
• C. $\Delta H^o=-20,\Delta S^o=-50$
• D. $\Delta H^o=-90,\Delta S^o=-20$

Answer 1

The correct option is C $\Delta H^o=-20,\Delta S^o=-50$

$\left(\Delta G\right)=$$\left(\Delta H\right)-T$$\left(\Delta S\right)$

$\text{from the above equation we can easily clearify that more the negative value of}$ $\left(\Delta S\right)$ $\text{increases most positive the value of}$$\left(\Delta G\right)$.

$\text{So option C is correct.}$