NBC 105 • Unit 412 min read★ High Exam Frequency
Greenhouse Effect, Acid Rain Chemistry & Ozone Layer Hole
Unit 4: Global Environmental Issues • Environment and Ecology
👨🏫 Professor's Mental Model: Earth's Thermal Blanket & Sunscreen
Greenhouse gases Earth ka blanket hain jo raat me garmi rok kar rakhti hain. Blanket mota hone se bukhar (Global Warming) ho raha hai! Stratospheric Ozone Earth ka UV sunscreen hai; CFCs use phad kar UV rays ko seedhe aane deti hain!
Greenhouse Effect & Climate Change
Key Greenhouse Gases: CO2 (60% impact), CH4, N2O, CFCs, Water vapor. Consequences: Polar ice cap melting, sea level rise, ocean acidification.
Acid Rain Chemistry & Effects
Rainwater with pH < 5.6 caused by industrial SO2 and NOx emissions reacting with atmospheric moisture:
SO2 + H2O -> H2SO3 | 2NO2 + H2O -> HNO3 + HNO2.
Corrodes marble monuments (Taj Mahal Stone Cancer) and acidifies lake ecosystems.
Ozone Layer Depletion & Montreal Protocol (1987)
CFCs released into stratosphere break down via UV light, freeing chlorine radicals: Cl* + O3 -> ClO* + O2. Single Cl radical destroys ~100,000 ozone molecules. Protected by the landmark Montreal Protocol.
🎯 University Exam Scoring Blueprint
- Write the chemical reactions for Acid Rain and Ozone depletion.
- Explain Stubble (Paddy Straw) burning and winter smog in North India.
Top Viva Questions on Greenhouse Effect, Acid Rain Chemistry & Ozone Layer Hole
1