Cu nu reactioneaza cu HCl.
Zn + 2 HCl => ZnCl2 + H2
65 g Zn...........6.022 * 10^23 molecule
x g Zn...............3.0115 * 10^23 molecule
x = 32.5 g Zn
m Cu = 100 - 32.5 = 67,5 g Cu
%Cu = m Cu/m aliaj * 100 = 67.5/100*100 = 67.5%
%Zn = m Zn/m aliaj * 100 = 32.5/100*100 = 32.5%
65 g Zn............136 g ZnCl2
32.5 g Zn............x g ZnCl2
x = 68 g ZnCl2