Explain why sodium hydroxide solution cannot be kept in aluminum containers and also write an equation for the reaction that may take place for the same?

1. The reaction of aluminum (Al) and sodium hydroxide (NaOH) is a reaction between a metal(Al) and a base(NaOH).
2. During a reaction between a metal and a base metal oxide is formed along with the very flammable hydrogen gas.
3. Sodium hydroxide (NaOH) solution cannot be kept in aluminum containers because when sodium reacts with aluminum it corrodes the metal and produce highly flammable hydrogen gas.

Chemical reaction:

$2\mathrm{Al}\left(\mathrm{s}\right)+2\mathrm{NaOH}\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\to 2{\mathrm{NaAlO}}_2\left(\mathrm{aq}\right)+3{\mathrm{H}}_2\left(\mathrm{g}\right)$

Therefore, sodium hydroxide cannot be kept in aluminum containers.