Question

(a): Which is the stronger base-the basic form of the indicator cresol red or the primary form of thymolphthalein?

Short answer

Thymolphthalein is a strong basethan the cresol red indicator in basic form.

Step-by-step solution

Step 1:Acid-Base definition.

The substance which donates H⁺ions is called acid, and the base is a substance that accepts H⁺ions from the solution.Indicators work because they react with water to produce the hydrogen cation H⁺ or hydronium ion H₃O⁺. The indicator is something whose molecule changes its color as a result of the reaction.

The pH indicator.

A substance that helps in changing the color in any solution over a constrained range of pH values is termed an acid-base indicator or a pH indicator. The indicator chemical needs to alter the color slightly to be noticed. A pH indicator has little effect on the acidity or alkalinity of a chemical solution when employed as a diluted solution.

A strong base is a basic form of thymolphthalein.

The cresol red indicator has a slightly alkaline pH of 7.2-8.8. This is near neutral pH. The thymolphthalein has alkaline pH of 9.4-10.6. This pH is alkaline. In the basic form, the solution’s basicity increases, the pH is greater than 9.4, and it becomes more basic. Due to that reason, thymolphthalein is a strong base than the cresol red indicator.