Khi cho 1/2hh vào HCl:
2Al+ 6HCl------->2AlCl3+ 3H2(1)
Khi cho 1/2hh vào HNO3
Cu+ 4HNO3------> Cu(NO3)2+ 2NO2+ 2H2O(2)
Al+6HNO3-------> Al(NO3)3+ 3NO2+ 3H2O(3)
nH2=0.15 mol
nNO2=0.5 mol
Theo PTHH(1)nAl=2/3nH2O=0.1 mol
Theo PTHH(3) nNO2=3nAl=0.3 mol
=>nNO2(2)=0.5-0.3=0.2 mol
Theo PTHH (2) nCu=1/2nNO2=0.1 mol
=> m=2(mAl+mCu)=2(0.1*27+0.1*64)=18.2 g