PTHH: Zn + 2 HCl -> ZnCl2 + H2
nZn=13/65=0,2(mol)
nH2=nZnCl2=nZn=0,2(mol)
a) V(H2,đktc)=0,2.22,4=4,48(l)
b) nCuO= 24/80=0,3(mol)
PTHH: CuO + H2 -to-> Cu + H2O
Ta có: 0,3/1 > 0,2/1 => CuO dư, H2 hết, tính theo nH2
=> nCu=nH2=0,2(mol)
=> mCu=0,2.64=12,8(g)
c) 2 H2 + O2 -to-> H2O
nO2= 1/2 . nH2= 1/2 . 0,2=0,1(mol)
=> m(O2,đktc)=0,1.22,4=2,24(l)