编号 | 物质 | 杂质 | 试剂 | 除杂操作方法 |
A | CuO | C(木炭) | 足量稀盐酸 | 过滤、洗涤、干燥 |
B | CaCl2溶液 | HCl | 过量CaCO3粉末 | 过滤 |
C | CO2 | CO | O2 | 点燃 |
D | NaNO3溶液 | NaCl | 过量AgNO3溶液 | 过滤 |
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

