Câu 1
$n_{H2}$ =0.4(mol)
Zn + H2SO4 → ZnSO4 + H2
(mol) x x
Mg + H2SO4 → MgSO4 +H2
(mol) y y
Theo bài ra ta có hệ : $\left \{ {{x+y=0.4} \atop {65x+24y=17.8}} \right.$ ⇒$\left \{ {{x=0.2} \atop {y=0.2}} \right.$
⇒$m_{muối}$= $m_{ZnSO4}$+ $m_{MgSO4}$=56.2(g)