(1)“快速晾干筷子,析出少量晶体”是通过
(2)制作棒棒糖时,小明将蔗糖加入热水中,用筷子稍作搅拌,观察到杯底还留有蔗糖固体,接着就进行过滤等后续操作,5天后却没有制得棒棒糖,杯中也没有晶体析出。棒棒糖制作失败的原因:最初配制的蔗糖溶液是
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