A.用酒精灯直接加热蒸发皿 |
B.测定“84”消毒液的pH,用洁净的玻璃棒蘸取少许“84”消毒液滴在pH试纸上 |
C.容量瓶、滴定管使用前均需用蒸馏水洗净、烘干、检查是否漏水 |
D.可用碱式滴定管量取25.00mLKMnO4标准溶液置于锥形瓶中 |

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

