nH2= 2.24/22.4=0.1 mol
Mg + H2SO4 --> MgSO4 + H2
0.1_____________________0.1
mMg= 0.1*24=2.4g
nSO2= 3.36/22.4=0.15 mol
Mg + 2H2SO4 --> MgSO4 + SO2 + H2O
0.1______________________0.1
Cu + 2H2SO4 --> CuSO4 + SO2 + H2O
0.05____________________0.15-0.1
mCu= 0.05*64=3.2g
mhhX= mMg + mCu = 2.4+3.2=5.6g