问题
选择题
If you can't find Jack, you can ___________ at 615-3329. [ ]
A. call him
B. call her
C. find him
D. talk her
答案
答案:A
If you can't find Jack, you can ___________ at 615-3329. [ ]
A. call him
B. call her
C. find him
D. talk her
答案:A
下列物质鉴别的实验方法错误的是( )
鉴别物质 | 方法 | |
A. | 过氧化氢和蒸馏水 | 分别加入MnO2,看是否有气泡 |
B. | 镁和锌 | 分别加入稀盐酸,看是否有气泡 |
C. | 二氧化碳、氧气和空气 | 将燃着的木条分别伸入瓶中,观察现象 |
D. | 活性炭和氧化铜 | 分别投入盛有红棕色二氧化氮气体的集气瓶中,观察现象 |