选项 | 实验目的 | 实验操作 |
A | 区别硬水和软水 | 取样,分别加入肥皂水,振荡 |
B | 鉴别炭粉、铁粉和氧化铜粉末 | 取样,分别滴加稀盐酸 |
C | 区分KOH溶液和Ca(OH)2溶液 | 取样,分别通入CO2 |
D | 除去N2中少量的O2 | 将混合气体通过装有铜丝网的玻璃管 |
A.A | B.B | C.C | D.D |

同类型试题

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


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

