Strong and weak electrolytes:

Electrolytes can be classified as strong or weak. This has nothing to do with their concentration but related to their extent of ionisation.

Strong electrolytes: The substances that are fully ionized in aqueous solutions are known as strong electrolytes, example for NaCl, HCl, NH₄Cl, KNO₃, HBr, etc.

Weak electrolytes: The substances that ionise only to a certain extent are known as weak electrolytes, example for HCN, CH₃COOH, etc.

The terms strong and weak are associative. The behaviour of electrolytes also depends on the nature of solvents, example for. NaCl behaves as strong electrolyte whereas acetic acid as a weak electrolyte in water. Alter, while dissolved in ammonia both NaCl and acetic acid show comparable behaviour towards electricity.