题目

化学反应速率是描述化学反应进行快慢程度的物理量。下面是某同学测定化学反应速率并探究其影响因素的实验。 Ⅰ.测定化学反应速率 该同学利用如图装置测定化学反应速率。 (1)除如图装置所示的实验用品外，还需要的一件实验用品是______________。(2)圆底烧瓶中所发生反应的离子方程式为___________。(3)若在2 min时收集到224 mL(已折算成标准状况)气体，可计算出该2 min内H＋的反应速率，而该测定值比实际值偏小，其原因是____________________________________。 完型填空，根据短文内容选择最佳答案。Life is not easy, so I’d like to say “When anything happens, believe in yourself. ” When I was a young boy, I was 1 shy to talk to anyone. My classmates often 2 me. I was sad but could do nothing. Later, 3 happened, and it changed my life. It was an English speech contest. My mother asked me to 4 it. What a terrible idea! It meant I had to speak 5 all the teachers and students of my school!“Come on, boy. Believe in yourself. You are sure to win. ” Then mother and I talked about many different topics. At last I 6 the topic “Believe in yourself”. I tried my best to remember all the speech and practiced it over 100 7 . With my mother’s great love, I did 8 in the contest. I could hardly believe my ears when the news came that I had won the first place. I heard the cheers (赞美) from the teachers and students. Those classmates 9 once looked down on me, now all said “congratulations!” to me. My mother hugged me and cried excitedly. 10 then, everything has changed for me. When I do anything, I try to tell myself to be sure and I will find myself. This is true not only for a person but also for a country.( )1. A. too B. so C. quite( )2. A. caught up with B. looked after C. laughed at( )3. A. nothing B. something C. everything( )4. A. take part in B. join C. get( )5 A. with B. to C. before( )6. A. brought B. thought C. chose( )7. A. words B. times C. sentences( )8. A. well B. good C. bad( )9. A. when B. which C. who( )10. A. Since B. Except C. From