Q. Illustrate Strengths of Acids and Bases?

Ans.

Acids and bases can be classified as strong or weak. If an acid or base is strong, it ionizes completely in water. On the other hand, if an acid or base is weak, it only ionizes partially in water.

For example. hydrochloric acid, HCl, is a strong acid while acetic acid, CH₃COOH, is a weak acid. An example of a strong base is sodium hydroxide, NaOH, while an example of a familiar weak base is ammonia, NH₃.

Note: Some substances are amphiprotic. This means they can act as an acid or a base depending on the conditions. In other words, they can either produce a proton or accept a proton (H⁺ ion).

Water is such an amphiprotic substance. It can produce an H⁺ ion and become OH^- or it can accept an H⁺ and become the hydronium ion, H₃O⁺:

                     H₂O -> H⁺ + 2OH^- 
                     H₂O + H⁺ -> H₃O⁺