问题
选择题
I hate people _______ talk much but do little. |
A. whom B. which C. who D. when |
答案
答案:C
I hate people _______ talk much but do little. |
A. whom B. which C. who D. when |
答案:C
下列涉及离子方程式书写的评价合理的是
选项 | 化学反应及离子方程式 | 评价 |
A | 醋酸钠溶于水:CH3COO-+H2O=CH3COOH+OH- | 正确 |
B | 实验室用浓盐酸与MnO2反应制Cl2: | 错误,反应物中HCl电离出的H+、Cl-比例为1:1 |
C | 硝酸铁溶液中加过量氨水:Fe3++3NH3·H2O= Fe(OH)3(胶体)+3NH4+ | 错误,Fe(OH)3应该是沉淀 |
D | NH4HCO3溶液与过量的NaOH溶液反应: HCO3-+OH-=CO32-+H2O | 正确 |