Here are simplified notes on Acids, Bases, and Salts:
Acids:
- Definition: Acids are substances that release hydrogen ions (H⁺) when dissolved in water.
- Examples: Lemon juice (citric acid), vinegar (acetic acid), stomach acid (hydrochloric acid).
- Properties: Sour taste, turn blue litmus paper red, react with metals to release hydrogen gas.
Bases:
- Definition: Bases are substances that release hydroxide ions (OH⁻) when dissolved in water, or accept H⁺ ions.
- Examples: Soap, baking soda (sodium bicarbonate), ammonia (NH₃).
- Properties: Bitter taste, feel slippery or soapy, turn red litmus paper blue.
Neutralization Reaction:
- When an acid reacts with a base, they neutralize each other to form salt and water.
- Example: Hydrochloric acid (HCl) + Sodium hydroxide (NaOH) → Sodium chloride (NaCl) + Water (H₂O).
pH Scale:
- Measures acidity or basicity of a solution.
- Range from 0 to 14: 0-6.9 is acidic, 7 is neutral, 7.1-14 is basic.
- Examples: Battery acid (pH 1), pure water (pH 7), bleach (pH 12).
Salts:
- Definition: Salts are compounds formed from the reaction of an acid with a base.
- Examples: Sodium chloride (NaCl), calcium carbonate (CaCO₃), potassium nitrate (KNO₃).
- Properties: Often crystalline solids, can be soluble or insoluble in water.
Common Salt:
- Sodium chloride (NaCl), obtained from seawater or mined from salt deposits.
- Used in cooking, preserving food, and as a seasoning.
Types of Salts:
- Normal Salts: Formed from strong acid + strong base (e.g., NaCl).
- Acidic Salts: Formed from strong acid + weak base (e.g., NaHSO₄).
- Basic Salts: Formed from weak acid + strong base (e.g., NaHCO₃).
Uses of Salts:
- Food preservation, flavoring, and seasoning.
- Industrial processes, water softening, and agriculture.
Importance in Nature:
- Acids and bases are crucial in biochemical processes (e.g., digestion).
- pH balance is essential for aquatic ecosystems and soil fertility.
Acid Rain:
- Formed when sulfur dioxide (SO₂) and nitrogen oxides (NOâ‚“) react with water in the atmosphere.
- Causes environmental damage to vegetation, water bodies, and buildings.
Summary:
- Acids release H⁺ ions, taste sour, and turn blue litmus paper red.
- Bases release OH⁻ ions, taste bitter, and turn red litmus paper blue.
- Salts are compounds from acid-base reactions, used widely in daily life.
Understanding acids, bases, and salts helps explain many chemical reactions and their impact on our environment and daily activities.