Question

Name the products formed when dilute $$\mathrm{HNO}{\phantom{A}}_3$$ is added to copper.

Answer 1

When diluted nitric acid is applied to copper, copper nitrate, water, and the colourless gas nitrogen monoxide are generated.

$$3\mathrm{Cu}+8\mathrm{HNO}{\phantom{A}}_3{\phantom{A}}_{(\mathrm{dil})}⟶\underset{\mathrm{Copper}\mathrm{nitrate}}{3\mathrm{Cu}(\mathrm{NO}{\phantom{A}}_3){\phantom{A}}_2}+4\mathrm{H}{\phantom{A}}_2\mathrm{O}+2\mathrm{NO}{\phantom{A}}^{-}$$

Nitrogen monoxide then combines with air, producing reddish-brown emissions of nitrogen dioxide.

$$2\mathrm{NO}+\mathrm{O}{\phantom{A}}_2⟶\underset{\mathrm{Nitrogen}\mathrm{dioxide}}{2\mathrm{NO}{\phantom{A}}_2}$$