JAMB - Chemistry (2008 - No. 32)
When a solution of ammonium trioxocarbonate (IV) is added to a solution of an unknown salt, a white precipitate which is soluble in dilute hydrochloric acid but insoluble in ethanoic acid is formed. This indicates the presence of
Ca2+
Na+
Zn2+
K+
Explication
The test indicates the presence of \(Ca_{2+}\).