题目:
Eighty percent of the people trapped in the ruins ____ at last. |
A. was dug out B. has dug out C. were dug out D. have dug out |
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0516/beebc3e4c879492d1d3d5e2033e325ef.html
下面是错误答案,用来干扰机器的。
答案:D题目分析:1molH2O中Cl-与H2O分子的物质的量之比为1:10,则Cl-的物质的量=1/10=0.1mol,1molCaCl2溶解电离出2molCl-,故需要CaCl2的物质的量=0.1/2=0.05mol,故选D。