Why is hydrochloric acid considered a strong acid?
Answer and explanation
Correct answer: It ionises almost completely in water
Acid strength is related to the extent of ionisation in water, not simply to how concentrated the acid is. Hydrochloric acid ionises almost completely: HCl + H2O → H3O+ + Cl−. This produces a high concentration of hydronium ions for a given concentration of acid, so HCl is classified as a strong acid. It is soluble in water and is neither a base nor a salt, which eliminates options B, C, and D.
Frequently asked questions
What is the correct answer to this question?
It ionises almost completely in water
Why is this the correct answer?
Acid strength is related to the extent of ionisation in water, not simply to how concentrated the acid is. Hydrochloric acid ionises almost completely: HCl + H2O → H3O+ + Cl−. This produces a high concentration of hydronium ions for a given concentration of acid, so HCl is classified as a strong acid. It is soluble in water and is neither a base nor a salt, which eliminates options B, C, and D.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
