Potential of Hydrogen (pH) Scale
What is the full form of pH?
The full form of pH is “Potential of Hydrogen”. pH is known as the negative logarithm of H+ ion concentration. Hence the meaning of the name pH is explained as the strength of hydrogen or power of hydrogen. pH describes the concentration of the hydrogen ions in a solution, which is the indicator of the acidity or basicity of the solution. The pH value on a pH scale varies from 0 to 14.
pH of Acid And Base
The pH of the solution ranges from 0 to 14.
- Solutions with a pH value varying from 0 to <7 on the pH scale are called acidic solutions.
- Solution with a pH value ranging from >7 to 14 is known as basic solutions.
- On a pH scale, solutions with a potential of hydrogen or a pH value equal to 7 are known as neutral solutions.
Solutions with a pH value of 0 are considered to be extremely acidic. Additionally, the acidity decreases as the pH value increase from 0 to 7, while solutions with a pH value equal to 14 are known to be strongly basic solutions. The acid and base intensity depends on the number of H+ and OH– ions produced. Acids furnishing more H+ ions are known to be strong acids, and vice versa.
Importance of pH
- A living organism can withstand only a limited range of pH changes, and any more pH adjustments will make life difficult. For example: in the case of acid rain, the pH of the water is less than 7. It decreases the pH of river water as it flows into a river which hinders the survival of marine life.
- The human stomach lining secretes hydrochloric acid, which helps digest food by activating certain enzymes. Antacids are used to neutralise the acid produced in the stomach in case of acid reflux.
- Often the bacteria present in our mouth lower the pH of our mouth by generating acids through food particle degradation. This results in the demineralisation of teeth and tooth decay. Therefore, we are told to clean our teeth and mouths since mouthwash neutralises the acid and helps in remineralisation. Fluoride toothpaste aids in remineralisation and prevents decay.
- In the case of a bee sting, we feel a lot of pain when the bee injects formic acid (methanoic acid) through its sting. Therefore, we are usually recommended to apply baking soda or other mild bases to the surface because it helps to neutralise the acid and maintain the pH.
