1. [tex]2Al + 3H_{2}SO_{4} \rightarrow Al_{2}(SO_{4})_3 + 3H_{2}[/tex]
2. Theo pt: nAl = 2/3 nH2 = 2/3 x 0.3 (mol) = 0.2 (mol) => mAl = 5.4 => mCu = 10 -5.4=4.6(g)
3. Theo pt: nH2SO4 = nH2 = 0.3 => mH2SO4 = 0.3 x 98 = 29.4 => mDdH2SO4 = (29.4 x 100)/20 = 147 (g)