已建立化学平衡的某可逆反应,当条件改变使化学平衡向正反应方向移动时,下列叙述正确的是 ①生成物的质量分数(百分含量)一定增加 ②生成物产量一定增加 ③反应物的转化率一定增加 ④反应物浓度一定降低 ⑤正反应速率一定大于逆反应速率 ⑥一定使用了催化剂 A.①② B.②⑤ C.③⑤ D.④⑥14.听第7段材料,回答第8至10题.8.Why does the woman call Mr Johnson?A.To introduce a job. B.To set up a laboratory. C.To go to college.9.How did the Town Job Center get to know Johnson?A.Johnson telephoned them. B.Johnson e-mailed them. C.Johnson helped them.10.What makes Johnson think more about it?A.The equipment. B.The employer. C.The working time.