Question

How do you identify conjugate acid base pairs?

Answer 1

Let us take the example of Bicarbonate being placed in water to create Carbonic Acid and Hydronium ions.

`HCO_3^(-) + H_2O -> H_2CO_3 + OH^-`
`Base + Acid -> Conj A + Conj B`

On the reactant side of the equation the water (`H_2O`) is the Acid as it is the hydrogen ion donor to the bicarbonate (`HCO_3^-`) which is the Base as it receives the hydrogen ion..

On the product side the Carbonic Acid (`H_2CO_3`) is the Conjugate Acid as it is the hydrogen donor to the Conjugate Base (`OH^-`) as it receives the hydrogen ion.

`HCO_3^(-) -> H_2CO_3`
`Base -> Conj A`
The Carbonic Acid (`H_2CO_3`) is the Conjugate Acid pair to the Base bicarbonate (`HCO_3^-`) .

`H_2O -> OH^-`
`Acid -> Conj B`

The Hydroxide (`OH^-`) is the Conjugate Base pair to the Water (H_2O#).

I hope this was helpful.
SMARTERTEACHER