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A strong electrolyte is a substance that completely dissociates into ions when dissolved in water. This means that it breaks apart into its constituent ions, which are fully separated and surrounded by water molecules. For example, in the dissolution of potassium sulfate (\text{K}_2 \text{SO}_4), it breaks down as follows:
\(\mathrm{K}_2 \mathrm{SO}_4\,(s) \longrightarrow 2 \mathrm{K}^+(aq) + \mathrm{SO}_4^{2-}(aq)\)
Since \text{K}_2 \text{SO}_4 completely dissociates into potassium ions (\text{K}^+) and sulfate ions (\text{SO}_4^{2-}), it is classified as a strong electrolyte. Other common strong electrolytes include:

• Strong acids like hydrochloric acid (\text{HCl})

A weak electrolyte is a compound that partially dissociates into ions in solution. Unlike strong electrolytes, they do not completely break apart. A classic example of a weak electrolyte is ammonia (\text{NH}_3). When \text{NH}_3 dissolves in water, it undergoes a reversible reaction:
\(\mathrm{NH}_3\,(g) + \mathrm{H}_2\mathrm{O}\,(l) \rightleftharpoons \mathrm{NH}_4^+(aq) + \mathrm{OH}^-(aq)\)
In this case, the reaction can go both ways, as indicated by the double arrows. Hence, not all \text{NH}_3 molecules will dissociate completely into \text{NH}_4^+ and \text{OH}^- ions, leading to the classification of \text{NH}_3 as a weak electrolyte.
Other common weak electrolytes include:

• Weak acids like acetic acid (\text{CH}_3\text{COOH})

A nonelectrolyte is a substance that does not produce ions when it dissolves in water. These substances dissolve as whole molecules without breaking up into ions. For example, glucose (\text{C}_6 \text{H}_{12} \text{O}_6) dissolves in water as follows:
\(\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6\,(s) \longrightarrow \mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6\,(aq)\)
Since the glucose molecules remain intact and do not dissociate into ions, it is classified as a nonelectrolyte. Some common types of nonelectrolytes include:

• Most organic compounds like ethanol (\text{C}_2\text{H}_5\text{OH})
• Sugars like sucrose (\text{C}_{12}\text{H}_{22}\text{O}_{11})