查阅资料:①Fe3C+2H23Fe+CH4;②3CH4+4Fe2O38Fe+6H2O+3CO2;③FeO+H2Fe+H2O;④碱石灰吸收H2O和CO2,不吸收CH4
(1)装配好实验装置后,先要
(2)加热前先通一段时间H2的目的是
(3)实验开始时应先对
(4)充分反应后还需称量哪些量,才能测定还原性铁粉中单质铁的含量?
(5)实验中,实际测得装置D增重的质量大于CH4与Fe2O3反应生成的H2O的质量,原因是
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