Discuss in brief Arrhenius concept of acids and bases.

Solution

Acid: According to Arrhenius an acid is a hydrogen-containing substance which dissociates to give hydrogen ions (H⁺) in its aqueous solution. For example substances such as HCl, HNO₃, CH₃COOH are acids.

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Acids such as HCl and HNO₃ which are almost completely ionised in aqueous solutions are known as strong acids, whereas acids such as CH₃COOH which are weakly ionised are called weak acids.
Base: According to Arrhenius, the base is a substance containing one or more hydroxide groups which dissociate to give hydroxyl ions (OH^–) in its aqueous solution.For example substances such as NaOH, KOH, Ca(OH)₂ are bases.