General Introduction: Importance of Chemistry
Chemistry is the central science that connects physics to biology and medicine. It studies matter at atomic and molecular levels, explaining how substances interact, combine, and change.
🔬 Key Definition: Chemistry is the science that deals with the composition, structure, properties, and transformations of matter.
Why Chemistry Matters
1. In Daily Life
- Food chemistry: Preservation, fermentation, nutrition
- Cleaning agents: Soaps, detergents, disinfectants
- Medicines: From aspirin to advanced antibiotics
2. In Industry
Example: Haber Process for Ammonia
N2(g) + 3H2(g) ⇌ 2NH3(g) (ΔH = -92.4 kJ/mol)
N2(g) + 3H2(g) ⇌ 2NH3(g) (ΔH = -92.4 kJ/mol)
- Petrochemicals: Plastics, synthetic fibers
- Agriculture: Fertilizers, pesticides
- Electronics: Silicon chips, batteries
3. In Environmental Protection
- Ozone layer protection (CFC alternatives)
- Water treatment technologies
- Carbon capture methods
Class 11 Focus Areas
This unit establishes fundamentals for:
• Stoichiometry: 2H2 + O2 → 2H2O
• Mole concept: n = N/NA (NA = 6.022×1023)
• Composition calculations: % mass = (mass element/mass compound)×100
• Mole concept: n = N/NA (NA = 6.022×1023)
• Composition calculations: % mass = (mass element/mass compound)×100
Career Pathways
- Healthcare: Pharmacy, biochemistry
- Research: Materials science, nanotechnology
- Industry: Chemical engineering, food technology