组别 | 加入的物质 | 处理 | 温度(℃) | 保温时长(min) | 加碘液后的现象 | |
甲 | 适量馒头碎屑 | 2mL唾液 | 搅拌 | 37 | 10 | ① |
乙 | 适量馒头碎屑 | 2mL清水 | 搅拌 | 37 | 10 | ② |
A.①变蓝、②不变蓝 | B.①不变蓝、②不变蓝 |
C.①不变蓝、②变蓝 | D.①变蓝、②变蓝 |
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