✔ 最佳答案
(a)
3Mg(s) + N2(g) → Mg3N2(s)
(b)
Mg3N2(s) + 3H2O(l) → 3MgO(s) + 2NH3(g)
(c)
3Mg(s) + N2(g) → Mg3N2(s)
Mole ratio Mg : Mg3N2 = 3 : 1
Molar mass of Mg = 24.3 g/mol
No. of moles of Mg used = 10/24.3 = 0.4115 mol
No. of moles of Mg3N2 formed = 0.4115 x (1/3) = 0.1372 mol
Molar mass of Mg3N2 = 24.3x3 + 14x2 = 100.9 g/mol
Mass of Mg3N2 = 0.1372 x 100.9 = 13.8 g
(d)
(1)
Mg3N2(s) + 3H2O(l) → 3MgO(s) + 2NH3(g)
Mole ratio Mg3N2 : MgO = 1 : 3
No. of moles of Mg3N2 used = 0.1372 mol
No. of moles of MgO formed = 0.1372 x 3 = 0.4116 mol
Molar mass of MgO = 24.3 + 16 = 40.3 g/mol
Mass of MgO formed = 0.4116 x 40.3 = 16.6 g
(2)
Mole ratio Mg3N2 : NH3 = 1 : 2
No. of moles of Mg3N2 used = 0.1372 mol
No. of moles of NH3 formed = 0.1372 x 2 = 0.2744 mol
Molar volume of NH3 in room conditions = 24 dm^3
Volume of NH3 formed = 0.2744 x 24 = 6.59 dm^3