Question

A metal M does not liberate hydrogen from acids but reacts with oxygen to give a black colour product. identify M and black colour product and also explain the
reaction of M with oxygen.

Answer 1

$$\begin{gathered} \mathrm{M}\mathrm{is}\mathrm{copper}\mathrm{and}\mathrm{black}\mathrm{coloured}\mathrm{product}\mathrm{is}\mathrm{copper}\left(\mathrm{II}\right)\mathrm{oxide}. \\ 2\mathrm{Cu}+{\mathrm{O}}_2\to 2\mathrm{CuO} \end{gathered}$$