Question
What is a degree of ionisation ?
Solution
Some substances when dissolved in water form positive and negative ions. The breaking of the substances into ions, when dissolved in a solvent, is called ionisation. The extent to which an electrolyte undergoes ionisation is expressed in terms of degree of ionisation and it may be defined as the fraction of electrolyte which dissociates into ions.
Mathematically,
Clearly, the degree of ionisation is taken per mole of an electrolyte. For example, if 0·5 mole weak acid HA ionises to give 0·02 mole H+ (aq) or 0·02 mole A– (aq), the degree of ionisation per mole of the electrolyte.HA would be
Mathematically,
Clearly, the degree of ionisation is taken per mole of an electrolyte. For example, if 0·5 mole weak acid HA ionises to give 0·02 mole H+ (aq) or 0·02 mole A– (aq), the degree of ionisation per mole of the electrolyte.HA would be
