题目

They are shocked to find that in this town the traffic rules are not strictly ________.        A. noticed             B. recommended    C. observed         D. concerned 答案：在某温度下，将3molA和2mol B充入一密闭容器中，发生反应：aA(g)＋B(g)C(g)＋D(g)，5min后达平衡，各物质的平衡浓度的关系为ca(A)·c(B)＝c(C)·c(D)。若在温度不变的情况下将容器的体积扩大为原来的10倍，B的转化率不发生变化，则B的转化率为A. 60%B. 40%C. 24%D. 4%