a)Zn+2HCl→ZnCl2+H2
b)m(HCl)=m(HCl+H2O):100×C%=7.8g
n(HCl)=m(HCl)÷M(HCl)=0.2 mol
theo PTPU:n(Zn)=0.5×n(HCl)=0.1 mol
→m(Zn)=n(Zn)×M(Zn)=6.5 g
c)theo PTPU:n(H2)=n(Zn)=0.1 mol
→v(H2)=n(H2)×22.4=2.24 lít
d)
theo PTPU:n(ZnCl2)=n(Zn)=0.1 mol
→m(ZnCL2)=n(ZnCl2)×M(ZnCl2)=13.5 g