题干
Rock music may nice to young people, but most old
people can't stand it.
A：hear
B：sound
C：look
D：listen
答案(点此获取答案解析）
B
H2O(g)＋CO(g)，反应所处的温度相同，但起始浓度不同。其中甲：CO2 = H2 =" a" mol；乙：CO2 =" a" mol ，H2 =" 2a" mol ；丙：CO2 =H2 =H2O(g)=" a" mol 。达到平衡时，CO2的物质的量由大到小的顺序是