题目

----How did you like Nick’s performance last night? ----To be honest, his singing didn’t _______to me much. A. appeal          B . belong        C refer            D. occur 答案：A已知金属铁和稀盐酸能发生下列反应：Fe+2HCl═FeCl2+H2↑，现有6.3g不纯的铁与足量稀盐酸反应，生成0.2g氢气，求铁粉中纯铁的质量分数是多少？