pH is defined as the measure of hydrogen ion concentration used to measure the acidity or alkalinity of a given solution.
Following is the equation that is used for calculating the pH:
pH = -log[H+]
Values of pH
- The range of the pH scale varies from 0 to 14
- Solutions with a pH value ranging from 0 to 7 on the pH scale are known as acidic, and the value of pH ranging from 7 to 14 on the pH scale are called basic solutions.
- Solutions having the value of pH equal to 7 on the pH scale are termed neutral solutions.
Examples
| Example | Acid / Base/ Neutral | pH value |
| Lemon Juice | Acid | 2 |
| Orange Juice | Acid | 3 |
| Water | Neutral | 7 |
| Sugar solution | Neutral | 7 |
| Baking soda | Base | 9 |
| Liquid Drain cleaner | Base | 13 |
Applications of pH
- To determine the strength of the solution.
- To identify the nature of the solution, whether acidic or basic
- To identify the type of soil in agriculture
- Used for environmental monitoring
