选项 | 实验目的 | 实验方法 |
A | 除去KCl固体中混有的MnO2 | 加适量水溶解、过滤、洗涤、干燥 |
B | 除去CO2中混有的CO | 将混合气体点燃 |
C | 除去N2中混有的O2 | 将混合气体通过炽热的炭层 |
D | 除去铜粉中混有的铁粉 | 加过量稀盐酸、过滤、洗涤、干燥 |
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