When aluminium foil reacts with sodium hydroxide, sodium aluminate is formed. Metals react with dilute acids to form metallic salts and hydrogen gas.
For example: Aluminium foil reacts with dilute hydrochloric acid to produce aluminium chloride and hydrogen gas.
The balanced chemical equation for the reaction is:
2Al(s) + 6HCl(aq) 2AlCl3(aq) + 3H2(g).
Aluminium is an amphoteric metal. It reacts with both acids and bases. The reaction is highly exothermic and produces a lot of heat. There is rapid evolution of hydrogen gas during this reaction.
