If Delta_r H^{ominus} and Delta_r S^{ominus} | vedclass

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Question

(B) The spontaneity of a reaction is determined by the Gibbs free energy change,given by the equation $\Delta_r G^{\ominus} = \Delta_r H^{\ominus} - T

Vedclass · Accepted Answer

$\Delta_r H^{\ominus} = 	ext{negative}; \Delta_r S^{\ominus} = 	ext{negative}; 	ext{non-spontaneous at low temperatures}$

Vedclass · Answer

(B) The spontaneity of a reaction is determined by the Gibbs free energy change,given by the equation $\Delta_r G^{\ominus} = \Delta_r H^{\ominus} - T \Delta_r S^{\ominus}$.For a reaction to be spontaneous,$\Delta_r G^{\ominus} $(A)$ If $\Delta_r H^{\ominus}  0$,then $\Delta_r G^{\ominus} = (-H) - T(+S) = (-H) - (T 	imes S)$,which is always negative at all temperatures. This is correct.$(B)$ If $\Delta_r H^{\ominus} $(C)$ If $\Delta_r H^{\ominus} > 0$ and $\Delta_r S^{\ominus} > 0$,then $\Delta_r G^{\ominus} = (+H) - T(+S)$. For spontaneity,$T > H/S$. Thus,it is non-spontaneous at low temperatures. This is correct.$(D)$ If $\Delta_r H^{\ominus} Therefore,the incorrect option is $(B)$.

If $\Delta_r H^{\ominus}$ and $\Delta_r S^{\ominus}$ are standard enthalpy change and standard entropy change respectively for a reaction,the incorrect option is

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