What is the chemical equation for the reaction between nitric acid and copper?

With dilute nitric acid:

3 Cu(s) + 8 HNO3(aq) → 3 Cu(NO3)2(s) + 2 NO(g) + 4 H2O(l)

With conc. nitric acid:

Cu(s) + 4 HNO3(aq) → Cu(NO3)2(s) + 2 NO2(g) + 2 H2O(l)

Concentrated NITRIC ACID reats with Copper ad follows.

Cu +4HNO3 ———->Cu(NO3)2 +2 NO2 +2H2O

Dilute NITRIC ACID reacts with copper as follows

3Cu +8HNO3 ——→ 3Cu(NO3)2 +2 No +4H2O.