组别 | 烧杯中的物质 | X溶液 |
① | CuSO4和Na2SO4溶液 | NaOH溶液 |
② | 铜锌合金 | 稀H2SO4 |
③ | 稀HNO3和稀H2SO4 | BaCl2溶液 |
④ | NaOH和Na2CO3溶液 | 稀盐酸 |
A.① | B.② | C.③ | D.④ |
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