题干

煤化工中常需研究不同温度下平衡常数、投料比及产率等问题.已知CO(g)+H2O(g)⇌H2(g)+CO2(g)的平衡常数随温度的变化如表:下列叙述正确的是(   )

温度/℃

400

500

830

1 000

平衡常数K

10

9

1

0.6

A:该反应的正反应是吸热反应

B:该反应达到平衡后,保持容器体积不变升高温度,正反应速率不变,容器内混合气体的压强不变

C:830℃时,在恒容反应器中按物质的量比n(CO):n(H2O):n(H2):n(CO2)=2:4:6:1投入反应混合物发生上述反应,初始时刻υ<υ

D:830℃时,在2 L的密闭容器中加入4 mol CO(g)和6 mol H2O(g)达到平衡时,CO的转化率是60%

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D

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