The Total solution for NCERT class 6-12
A reaction, A + B → C + D + q isfound to have a positive entropy change. The reaction will be
(i) possible at hightemperature
(ii) possible only at lowtemperature
(iii) not possible at anytemperature
(iv)possible at any temperature
For a reaction to be spontaneous, ΔG shouldbe negative.
ΔG = ΔH – TΔS
According to the question,for the given reaction,
ΔS = positive
ΔH = negative (since heat isevolved)
⇒ ΔG = negative
Therefore, the reaction isspontaneous at any temperature.
Hence,alternative (iv) is correct.