Question

Question #b54aa

Answer 1

A Bronsted-Lowry base.

Explanation:

An Arrhenius base is a species than ionises in water to produce `OH^-` ions. Since `CaCO_3` contains no `OH^-` at all, it does not fulfil the definition of an Arrhenius base.

On the other hand, a Bronsted-Lowry base is a species that can accept a proton or `H^+` ion from a Bronsted-Lowry acid. The carbonate ion is able to take in protons to firstly form the bicarbonate ion and then form carbonic acid.

`CO_3 ^ (2-) + H^+ -> HCO_3 ^-`
`HCO_3 ^- + H^+ -> H_2 CO_3`

Carbonic acid is in equilibrium with `CO_2` and `H_2 O`.