[[1]] is an amphoteric oxide that is yellow when hot and white when cold.

Zinc is an amphoteric oxide which is yellow when hot and white when cold. 

As zinc oxide reacts with both acids and bases, hence, is amphoteric in nature.

$$\begin{gathered} \mathrm{ZnO}+2\mathrm{HCl}\to {\mathrm{ZnCl}}_2+{\mathrm{H}}_2\mathrm{O} (\mathrm{Reaction} \mathrm{with} \mathrm{acid}) \\ 2\mathrm{ZnO}+2\mathrm{NaOH}\to {\mathrm{Na}}_2{\mathrm{ZnO}}_2+{\mathrm{H}}_2\mathrm{O} (\mathrm{Reaction} \mathrm{with} \mathrm{base}) \end{gathered}$$