Question

The hydrangea bloomed is pink in colour, hence the nature of the soil in which it
grows is:
A. Acidic in nature
B. Basic in nature
C. Neutral in nature
D. Data insufficient

Answer 1

Hint:Hydrangea is the type of inflorescence and is not the true flower, the sepals and the leaves are modified and they make up most of the bloom and are pink in colour. This in turn depends on the pH of the soil.

Complete step by step answer:
The pink colour of the Hydrangea flower gives an indication about the nature of the soil and the nature of the soil can be determined by the pH scale but the physical colour is also a major parameter to be considered in this context. The measure of the acidity and basicity of the solution is known as pH. It is usually measured for three kinds of solutions or substances that are acidic, basic and neutral solutions, the acidic solutions contain $H^+$ ions, basic solutions contain $OH^-$ and in the neutral solutions both the ions are equal in number thus the solution is neutral in nature.

The range of the pH scale varies from 0-14, 0-6 solution ranges are acidic in nature, 8-14 are basic in nature and 7 pH, number is for the solution which is neutral in nature, pure water has a pH of 7. With the increase on the range of the pH scale the basicity of the solution increases. Usually the Hydroxyl ions concentration is calculated with the help of the pH measurements. Since the colour pink occurs in the basic range of the pH paper thus the soil will be basic in nature where the plant will grow.
Thus the option B is the correct answer.

Note:
The availability of the Aluminium ions in the soil is the main factor on which the colour of the Hydrangea ultimately depends. The aluminium ions are more mobile in the acidic type of soil since they are easily taken up by the other ions in that form.