How does dissociation affect conductivity?

1 Answer
Jun 12, 2014

Dissociation influences electrical conductivity. The greater the percentage of dissociation for ionic compounds or for acids and bases, the stronger the conductivity.

Covalent compounds, such as sucrose (#C_12H_22O_11#), do not dissociate in aqueous solutions. It, therefore, is classified as an electrolyte.

Ionic compounds, such as sodium chloride, dissociate completely into sodium and chloride ions. Since ions carry charge in aqueous solutions ( sodium is positively charged and chlorine is negatively charged) they are able to conduct electricity.

Strong acids and strong bases dissociates completely and are therefore strong electrolytes.
Hydrochloric acid is a strong acid and dissociates completely to form hydrogen and chloride ions.
Sodium hydroxide, a strong base, dissociates completely to form sodium ions and hydroxide ions.

A weak acid, such as acetic acid (#HC_2H_3O_2#), hardly dissociates. There are very hydrogen and acetate ions.
The most common species is the undissociated acid.

Since most of the acid does not break apart or dissociate, this is a weak electrolyte and therefore hardly conducts electricity.