| 物质 | 方法1 | 方法2 |
A | 甲烷和一氧化碳 | 将气体点燃观察现象 | 分别通入灼热的氧化铜,观察现象 |
B | 碳酸钠和硫酸铵 | 取样,溶解后分别滴入无色酚酞溶液,观察现象 | 取样,分别加Ca(OH)2固体,研磨后闻气味 |
C | 酒精和白醋 | 取样,品尝二者的味道 | 取样后分别点燃,观察现象 |
D | 木炭粉和氧化铜 | 取样,分别加入稀H2SO4,观察现象 | 观察物质的颜色 |
A.A | B.B | C.C | D.D |
![](http://static.xuejinqu.com/images/y-prise.png)
同类型试题
![](http://static.xuejinqu.com/images/medal.png)
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
![](http://static.xuejinqu.com/images/avatar.png)
![](http://static.xuejinqu.com/images/avatar.png)
y = sin x, x∈R, y∈[–1,1],周期为2π,函数图像以 x = (π/2) + kπ 为对称轴
y = arcsin x, x∈[–1,1], y∈[–π/2,π/2]
sin x = 0 ←→ arcsin x = 0
sin x = 1/2 ←→ arcsin x = π/6
sin x = √2/2 ←→ arcsin x = π/4
sin x = 1 ←→ arcsin x = π/2
![](http://static.xuejinqu.com/images/avatar.png)
![](http://static.xuejinqu.com/images/avatar.png)