选项 | 实验目的 | 实验操作或方法 |
A | 鉴别稀硫酸和氯化钠溶液 | 滴加酚酞溶液 |
B | 从粗盐中得到纯净的氯化钠 | 溶解、过滤、洗涤、干燥 |
C | 鉴别K2SO4、Cu(NO3)2、Ba(OH)2、NaOH | 不另加试剂 |
D | 除去CO2中含有的少量CO | 点燃 |
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

