HCl + Mg = HCl + Zn = HCl + Fe = HCl + CaCO3 = Zn + HCl = H2O2 + MnO2

Question

HCl + Mg =
HCl + Zn =
HCl + Fe =

HCl + CaCO3 =

Zn + HCl =

H2O2 + MnO2

Answer 1

ZN + HCl = ZNCl2 + H2
Mg + HCl → MgCl2 + H2Fe + HCl = FeCl2 + H2 
CaCO3 + 2HCl → CaCl2 + CO2 + H2O
Zn + HCl = ZnCl2 + H2
H2O2+MnO2= MnO+H2O+O2