①分别向质量为ag的镁粉和ag的铁粉中逐滴加入相同溶质质量分数的稀盐酸至过量
②向一定质量盐酸中逐滴加入与盐酸等质量、等溶质质量分数的NaOH溶液
③向一定量的氢氧化铜粉末中逐渐加入稀硫酸至过量
④煅烧一定量的石灰石样品(假设杂质不参与反应),y轴表示固体中杂质的质量分数
A.③④ | B.①② | C.①③ | D.②④ |
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