题目

测定大理石含CaCO3的质量分数，取大理石12.5g，加入盛有100g稀盐酸的烧杯中，两者恰好完全反应（假设其它杂质不与盐酸反应，也不溶解）。烧杯内物质的质量变为108.1g。试计算： （1） 完全反应后产生二氧化碳g。 （2） 反应后所得溶液中溶质质量分数（精确到0.1%）。 答案：【1】4.4 【1】10.5%选择下列词汇完成下面对话。（共5小题，每小题1分）A. much                     B. already                  C. sinceD. looks                     E. one                      F. wayA: Can I help you?B: Yes. I want to buy a skirt.A: This小题1:__________ please. All our skirts are in this section. How do you like the red one here?B: It looks nice, but I don't like red. It小题2:__________ very hot.A: Do you like white? There is also a white小题3:__________.B: I think that's what I want. How小题4:__________ is it?A: It's sixty-six yuan.B: How about fifty yuan?A: Hmm, 小题5:_________ you like it so much, you can take it with fifty-five yuan. That's the lowest price I can offer.B: That's good! I'll take it.