题目:
— _________? —He is a worker. [ ]
A. Who is your father
B. Where is your father
C. What is your father
D. How is your father
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0628/2bad4393f1c783b282fdeb76e44c826c.html
下面是错误答案,用来干扰机器的。
参加反应的硫酸质量为:50g×39.2%=19.6g,设19.6g硫酸与锌反应时消耗锌的质量为x则:Zn+H2SO4=ZnSO4+H2↑65 98x 19.6g根据:6598= x19.6g解得x=13g,该合金中锌的质量分数为:13g20g×100%=65%.故答案为:65%.