a)
2X + 2nHCl → 2XCln + nH2
nH2 = 3,36:22,4 = 0,15 mol => nX = \(\dfrac{0,3}{n}\) mol
<=> MX = \(\dfrac{m_X}{n_X}\)= 12n (g/mol)
=> Với n = 2 , Mx = 24(g/mol) là giá trị thỏa mãn
<=> X là magie (Mg)
b)
2Mg + O2 → 2MgO
2Cu + O2 → 2CuO
nMg= 3,6:24 = 0,15 = nMgO
nCu = 3,2:64= 0,05 = nCuO
=> mOxit = mMgO + mCuO = 0,15.40 + 0,05.80 = 10 gam
Bài 2:
X + nH2O → X(OH)n + \(\dfrac{n}{2}\)H2
nH2 = 5,6:22,4 = 0,25 mol => nX = \(\dfrac{0,5}{n}\) mol <=> mX = \(\dfrac{0,5.M_X}{n}\) = a gam
4X + nO2 → 2X2On
nO2 = 4,48:22,4 = 0,2 mol => nX = \(\dfrac{0,8}{n}\)mol
<=> b = \(\dfrac{0,8.M_X}{n}\) (gam)
=> \(\dfrac{a}{b}\)= \(\dfrac{0,5.M_X}{n}\):\(\dfrac{0,8.M_X}{n}\)= \(\dfrac{5}{8}\)