pH Scale
Understanding pH Scale
- The pH scale is used to measure the acidity or alkalinity of a solution.
- The scale ranges from 0 to 14, where 0 is strongly acidic, 14 is strongly alkaline, and 7 is neutral.
- Each step on the pH scale represents a tenfold difference in acidity or alkalinity.
- Most biological processes occur at a pH close to 7.
pH Indicators
- pH indicators, such as litmus paper or universal indicator, are used to determine the pH of a substance.
- Litmus paper turns red in acid and blue in alkali.
- Universal indicator changes multiple colours across the pH scale to give a more precise pH value.
Acids and Bases on pH Scale
- Acids have a pH less than 7. The strength of the acid increases as the pH value decreases.
- Bases have a pH more than 7. The strength of the base increases as the pH value increases.
- Neutral substances like pure water have a pH of 7.
Impact of Concentration and Temperature
- The concentration of the hydrogen ions (H+) or hydroxide ions (OH-) in a solution determines its pH.
- Temperature can also affect the pH, although this is less commonly considered in basic studies.
Role of pH in Everyday Life
- pH plays a crucial role in everyday life from digestive systems to gardening to swimming pools.
- Many products, such as cleaning supplies or cosmetics, have pH values indicated on their labels.
- Hydrangeas, for instance, change colour based on the pH of the soil they are grown in.
- It is essential to maintain a certain pH in swimming pools to prevent bacterial growth and maintain skin health.