A.量取2 mL 斐林试剂时应优先选用5 mL 量筒而不用10 mL 量筒 |
B.隔水加热时,试管中液体的液面应低于烧杯中水的液面 |
C.在组织样液中加入斐林试剂后试管内液体呈现无色,加热后变成砖红色 |
D.实验结束时将剩余的斐林试剂装入棕色瓶,以便长期保存备用 |

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

