Understanding Bases
📚 Key Concepts
🔹 Real-Life Example
When you wash your hands with soap, it feels slippery and has a bitter taste (though you shouldn’t taste it!). This is because soap is basic in nature. Window cleaners, baking soda, and antacids are all examples of bases. They neutralize acids and have properties opposite to acids.
Base: Bases are substances that release hydroxide ions (OH⁻) when dissolved in water. They have a bitter taste, feel soapy to touch, and turn red litmus paper blue.
Alkali: Water-soluble bases are called alkalis. All alkalis are bases, but not all bases are alkalis.
🧪 Important Concepts
🔸 Key Characteristics of Bases
- Bitter taste and soapy feel
- Turn red litmus paper blue
- Conduct electricity in aqueous solution
- React with acids to form salt and water
- Release OH⁻ ions in water
- React with metals to produce hydrogen gas
🔸 Classification of Bases
Based on Strength:
- Strong Bases: Completely ionize in water (NaOH, KOH, Ca(OH)₂)
- Weak Bases: Partially ionize in water (NH₄OH, Mg(OH)₂)
Based on Acidity:
- Monoacidic: Release one OH⁻ ion (NaOH, KOH)
- Diacidic: Release two OH⁻ ions (Ca(OH)₂, Mg(OH)₂)
- Triacidic: Release three OH⁻ ions (Al(OH)₃, Fe(OH)₃)
🔍 Advanced: Base Applications
- NaOH: Soap manufacturing, paper industry
- Ca(OH)₂: Whitewashing, water treatment
- Mg(OH)₂: Antacid (milk of magnesia)
- NH₄OH: Household cleaners