Cu⁰ + 2 HN^VO₃ + 2 HCl → Cu^IICl₂ + 2 N^IVO₂ + 2 H₂O

This is an oxidation-reduction (redox) reaction:

Cu⁰ - 2 e^- → Cu^II (oxidation)

2 N^V + 2 e^- → 2 N^IV (reduction)

Change the oxidation states

Search by reactants (Cu, HNO₃, HCl)

1.	Cu + HNO3 + HCl → CuCl2 + NO2 + H2O
2.	Cu + HNO3 + HCl → CuCl2 + NO + H2O
3.	Cu + HNO3 + HCl + H2O → CuCl*2H2O + NO
4.	Cu + HNO3 + HCl + H2O → CuCl2*2H2O + NO

Search by products (CuCl₂, NO₂, H₂O)

1.	Cu + HNO3 + HCl → CuCl2 + NO2 + H2O

Search by reactants (Cu, HNO₃, HCl) and by products (CuCl₂, NO₂, H₂O)

1.	Cu + HNO3 + HCl → CuCl2 + NO2 + H2O