Mg + 2HCl ==> MgCl2 + H2
0,1...........0,2..............0,1...................0,1
ZnO + 2HCl ==> ZnCl2 + H2O
0,05.......0,1...........0,05
nH2= 2,24/22,4= 0,1 (mol)
==> mMg= 0,1x24= 2,4 (g)
==> mZnO= 6,45-2,4= 4,05 (g) ==> nZnO= 4,05/81=0,05 (mol)
==> nHCl= 0,2 + 0,1= 0,3 (mol)
==> mHCl= 0,3x36,5= 10,95 (g)
==> mddHCl= (mctx100)/C%=(10,95x100)/7,3=150 (g)
mdd sau phản ứng= 6,45+150 - 0,2=156,25 (g)
mMgCl2= 0,1x95=9,5 (g)
==> C%MgCl2= (mct/mdd)x100= (9,5/156,25)x100= 6,08%
mZnCl2= 0,05x136= 6,8 (g)
==> C%ZnCl2= (mct/mdd)x100=(6,8/156,25)x100=4,352%