选项 | 操作和现象 | 结论 |
A | 向苯酚溶液中滴加浓溴水,产生白色沉淀 | 苯环使羟基变活泼 |
B | 向含淀粉的溶液中滴加溶液,溶液变蓝色 | 氧化性: |
C | 浊液中加入氨水,浊液变澄清溶液 | 氨水具有强碱性 |
D | 向溶液中滴加溶液,产生蓝色沉淀 | 已变质 |
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