问题
选择题
Liu Xiang can't attend the Political Consultative Conferences ____ in Beijing due to training. [ ]
A. to hold
B. held
C. to be held
D. being held
答案
答案:D
Liu Xiang can't attend the Political Consultative Conferences ____ in Beijing due to training. [ ]
A. to hold
B. held
C. to be held
D. being held
答案:D
离子检验的常用方法有三种:
检验方法 | 沉淀法 | 显色法 | 气体法 |
含义 | 反应中有沉淀产生或溶解 | 反应中有颜色变化 | 反应中有气体产生 |
A.NH4+:气体法
B.I-:沉淀法
C.Fe3+:显色法
D.Ca2+:气体法