问题
选择题
— Do you know whether they talked about their work or their family?
— As matter of fact, I couldn’t hear it clearly, as they talked in whisper. [ ]
A. the, a
B. the, the
C. a; a
D. a; the
答案
答案:C
— Do you know whether they talked about their work or their family?
— As matter of fact, I couldn’t hear it clearly, as they talked in whisper. [ ]
A. the, a
B. the, the
C. a; a
D. a; the
答案:C
下列实验“操作和现象”与“结论”对应关系正确的是
操作和现象 | 结论 | |
A | 向NaCl溶液先滴加少量AgNO3溶液,后滴加少量NaI溶液,先有白色沉淀,后变成黄色沉淀 | 说明Ksp(AgI)<Ksp(AgCl) |
B | 将SO2通人品红溶液中,红色褪去 | 说明SO2具有漂白性 |
C | 向FeCl3、CuCl2混合溶液加铁粉,有红色固体析出 | 说明氧化性:Cu2+>Fe3+ |
D | 向某溶液先滴加硝酸酸化,再滴加BaCl2溶液,有白色沉淀生成 | 该溶液中一定含有Ag+ |