22) Which of the followingprocesses have a AS > A) CH30H(l) — CH30H(s)B) N2(g) + 3 H2(g) — 2 NH3(g)C) CH4(g) + H20(g) — CO(g) +3 H2(g)D) Na2C03(s) + H20(g) + C02(g) — 2 NaHC03(s)All of the above processeshave a DS > 0

22) Which of the followingprocesses have a AS > A) CH30H(l) — CH30H(s)B) N2(g) + 3 H2(g) — 2 NH3(g)C) CH4(g) + H20(g) — CO(g) +3 H2(g)D) Na2C03(s) + H20(g) + C02(g) — 2 NaHC03(s)All of the above processeshave a DS > 0
22) Which of the followingprocesses have a AS >
A) CH30H(l) — CH30H(s)
B) N2(g) + 3 H2(g) — 2 NH3(g)
C) CH4(g) + H20(g) — CO(g) +3 H2(g)
D) Na2C03(s) + H20(g) + C02(g) — 2 NaHC03(s)
All of the above processeshave a DS > 0

22) Which of the followingprocesses have a AS > A) CH30H(l) — CH30H(s)B) N2(g) + 3 H2(g) — 2 NH3(g)C) CH4(g) + H20(g) — CO(g) +3 H2(g)D) Na2C03(s) + H20(g) + C02(g) — 2 NaHC03(s)All of the above processeshave a DS > 0
这题问的是哪个是熵增的反应
答案是C
A是液体变成固体的过程,因为液体分子运动范围广,固体分子受晶格束缚,所以凝固的过程属于熵减
B数一下反应前后气体计量数变化,因为反应后气体减少,所以也属于熵减过程.这里气体的具体种类不用考虑,因为其体分子运动范围极广,而分子本身又极小.
D反应后有气体被吸收,跟B是类似的情况,所以也属于熵减过程.而且在D中气体变成固体,熵值减少更甚.