20. For the reaction \( A + B \rightarrow C + D \), \( \Delta H^\circ = +40 \) kJ and \( \Delta S^\circ = +50 \) J/K. Therefore, the reaction under standard conditions is
(A) spontaneous at temperatures less than 10 K.
(B) spontaneous at temperatures greater than 800 K.
(C) spontaneous only at temperatures between 10 K and 800 K.
(D) spontaneous at all temperatures.
(E) nonspontaneous at all temperatures.
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統計: 尚無統計資料
統計: 尚無統計資料