* Electrolytes are substances that conduct electricity when dissolved in water. This happens because they dissociate into ions.

* Strong electrolytes dissociate almost completely into ions when dissolved.

* Weak electrolytes only partially dissociate into ions, meaning they exist in a solution as a mixture of ions and undissociated molecules.

Carbonic acid (H2CO3) is a weak acid. This means it only partially ionizes in water, forming hydrogen ions (H+) and bicarbonate ions (HCO3-):

H2CO3(aq) ⇌ H+(aq) + HCO3-(aq)

The equilibrium lies heavily towards the left, meaning that most of the H2CO3 remains undissociated. This limited ionization is why carbonic acid is a weak electrolyte.