1.空气中各组分气体体积分数最大的是
A.氧气 | B.氮气 | C.二氧化碳 | D.稀有气体 |
A.氧分子体积变小 | B.氧分子质量变小 |
C.氧分子数目变少 | D.氧分子间空隙变小 |
A.组装仪器 | B.检查气密性 |
C.加热固体 | D.氧气验满 |
A.酒精灯 | B.水槽 | C.集气瓶 | D.锥形瓶 |
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