问题
选择题
____ the Internet is bridging the distance between people, it may also be breaking some families or
will cause other family problems.[ ]
A. When
B. If
C. While
D. Since
答案
答案：C
搜题请搜索小程序“爱下问搜题”
____ the Internet is bridging the distance between people, it may also be breaking some families or
will cause other family problems.[ ]
A. When
B. If
C. While
D. Since
答案：C
下表为某兴趣小组用两种方法来鉴别物质的设计方案，其中完全正确的是（ ）
| 需要鉴别的物质 | 所加试剂或方法 | ||
| 方法1 | 方法2 | ||
| A | 一氧化碳和二氧化碳 | 通过灼热的氧化铜 | 点燃 |
| B | 食盐水和蒸馏水 | 观察颜色 | 尝味道 |
| C | 黄金和黄铜 | 浸入硝酸银溶液中 | 灼烧 |
| D | 软水和硬水 | 加肥皂水 | 取样蒸干 |
A．A正确
B．B正确
C．C正确
D．D正确