ACIDS, BASES & SALTS

PRERNA FOR IAS

ACIDS, BASES & SALTS

1. Acids

Acids are substances that release hydrogen ions (H⁺) in water. Common examples include hydrochloric acid, sulphuric acid, nitric acid, and acetic acid. Acids taste sour, turn blue litmus red, react with metals to produce hydrogen gas, and conduct electricity in aqueous solutions. They are widely used in industries and laboratories.

2. Bases

Bases are substances that release hydroxide ions (OH⁻) in water. Examples include sodium hydroxide, potassium hydroxide, and calcium hydroxide. Bases taste bitter, feel soapy, turn red litmus blue, and generally have a pH greater than 7. They are used in soap making, cleaning products, and industries.

3. Salts

Salts are compounds formed when acids react with bases in a neutralisation reaction. Examples include sodium chloride, copper sulphate, sodium carbonate, and sodium bicarbonate. Salts have various uses in food, agriculture, medicine, and industry. Their properties depend on the acid and base from which they are formed.

4. Indicators

Indicators are substances that help identify whether a solution is acidic, basic, or neutral by changing colour. Common indicators include litmus, phenolphthalein, methyl orange, and turmeric. They are widely used in laboratories and educational experiments to determine the nature of chemical solutions quickly and accurately.

5. Chemical Reactions

Important reactions involving acids and bases include metal-acid reactions producing hydrogen gas, acid-carbonate reactions producing carbon dioxide, and neutralisation reactions forming salt and water. These reactions have practical applications in industries, laboratories, agriculture, and environmental management. Understanding them helps explain many natural and industrial processes.

6. pH Scale

The pH scale measures the acidity or alkalinity of a solution from 0 to 14. Values below 7 indicate acids, 7 is neutral, and above 7 indicates bases. The pH scale is important in biology, agriculture, medicine, and environmental studies because it affects many chemical processes.

7. Importance of pH in Daily Life