- The metals must include zinc and aluminium, their oxides and their hydroxides, which react with caustic alkalis (NaOH, KOH), showing the amphoteric nature of these substances.
Name the metal hydroxides which are :
(a) Insoluble (b) Soluble in
(i) Caustic soda solution (ii) Ammonium hydroxide solution.
Choose the most appropriate answer from the following list of oxides which fit the description
[SO2, SiO2, Al2O3, MgO, CO, Na2O]
An oxide which dissolves in water forming an acid