Illustrate how copper metal can give different products on reaction with HNO3.

Concentrated nitric acid is a strong oxidizing agent. It is used for oxidizing most metals. The products of oxidation depend on the concentration of the acid, temperature, and also on the material undergoing oxidation. 3Cu+8HNO3(dilute)3Cu NO32+2NO+4H2O Cu+4HNO3concCuNO32+2NO2+2H2O