Question

copper+conc.nitric acid=copper nitrate + nitrogen-di-oxide+water.Balance it​

Answer 1

Nitric acid reacts with copper according to the reaction: 4 HNO3(l) + Cu(s) ==> Cu(NO3)2(s and aq) + 2 NO2(g) + 2 H2O(l) The copper nitrate salt that forms is a deep blue color. The nitrogen dioxide is a maroon vapor.