问题
选择题
— Whose ball is this?
— It's _____.[ ]
A. Jim's and Tom's
B. Tom's and Jim
C. Jim and Tom's
D. Jim and Tom
答案
答案:C
— Whose ball is this?
— It's _____.[ ]
A. Jim's and Tom's
B. Tom's and Jim
C. Jim and Tom's
D. Jim and Tom
答案:C
下图装置可用于收集气体X并验证其某些化学性质,你认为正确的是( )
选项 | 气体 | 试剂 | 现象 | 结论 |
A. SO2 酸性KMnO4溶液 溶液褪色 SO2有氧化性 B. C2H4 溴水 溶液褪色 能发生加成反应 C. X 澄清石灰水 溶液变浑浊 X不一定是CO2 D. Cl2 紫色石蕊试液 溶液先变红后褪色 Cl2有酸性和漂白性 |