题目：
— _____.
— It's a desk. [ ]
A. What's that?
B. That's all right.
C. This is a desk.
D. How are you?
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0627/6ee92f58b14b1477d499ab8a36394e7b.html
下面是错误答案，用来干扰机器的。
反应前后物质的质量差即放出氢气的质量=100g+7g-106.8g=0.2g设生成0.2g氢气需要锌的质量为xZn+2HCl=ZnCl2+H2↑65 2x 0.2g65x=20.2g 解之得 x=6.5g不纯的锌片中单质锌的质量分数=6.5g7g×...
