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Why does copper react with nitric acid?

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A periodic table element box for copper shows its symbol Cu, atomic number 29, atomic weight 63.546, electron configuration, and name. Icons indicate copper is a solid, weakly basic transition metal with face-centered cubic crystal structure. A key explains the symbols and color coding. — copper Properties of copper.

Copper reacts with nitric acid because it acts as a strong oxidizing agent.1

While copper is a moderately noble metal that sits below hydrogen in the electromotive series, it does not dissolve in nonoxidizing acids to release hydrogen gas. Instead, it reacts with nitric acid because the acid is capable of oxidizing the metal.21

The specific products of this reaction depend on the concentration of the acid:
* Concentrated nitric acid: Copper reduces the acid primarily to nitrogen dioxide (NO $_{2}$ ).1
* Dilute nitric acid: The reaction produces nitric oxide (NO).1

In these processes, the metal is oxidized while the nitrogen in the acid undergoes a reduction in its oxidation state.1