题干

I2在KI溶液中存在下列平衡:I2(aq)+I(aq)═I3(aq).测得不同温度下该反应的平衡常数如下表:

t/℃

5

15

25

35

50

K

1 000

850

690

625

400

下列说法正确的是(   )

A:反应I2aq)+Iaq═I3aq的△H>0

B:利用该反应可以除去硫粉中少量的碘单质

C:在上述平衡体系中加入苯,平衡不移动

D:25℃时,向溶液中加入少量KI固体,平衡常数K小于690

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答案(点此获取答案解析)

B

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