a) nH2=1,12/22,4=0,05(mol)
PTHH: Zn +2 HCl -> ZnCl2 + H2
0,05____0,1_____0,05____0,05(mol)
=>mZn= 0,05.65= 3,25(g)
b) => %mZn= (3,25/20).100=16,25%
=>%mZnO=100% - 16,25%= 83,75%
c) mZnO= 20 - 3,25= 16,75(g) => nZnO= 16,75/81= 67/324(mol)
PTHH: ZnO +2 HCl -> ZnCl2 + H2O
67/324______67/162(mol)
=> mddHCl= [(67/162+ 0,1). 36,5]: 14%=133,898(g)