Natural Resources (VI–VIII) • Topic 3 of 3

Coal, Petroleum & Sources of Energy

The NCERT Class VIII chapter 'Coal and Petroleum' is a CTET regular, and the core idea is the renewable/non-renewable split. Renewable (inexhaustible) resources are replenished by nature in a short time — sunlight, wind, flowing water and biomass. Non-renewable (exhaustible) resources exist in fixed amounts and will run out — coal, petroleum and natural gas, the three fossil fuels. Fossil fuels formed from the remains of dead plants and animals buried under layers of rock for millions of years, under high heat and pressure. Coal formed mainly from ancient plants (the process is called carbonisation); petroleum and natural gas formed from tiny dead sea organisms. Because they take millions of years to form but are consumed in moments, fossil fuels are non-renewable and finite — a point CTET phrases as 'exhaustible'. Petroleum is separated by fractional distillation in a refinery into products such as petrol, diesel, kerosene, LPG and bitumen — petroleum is nicknamed 'black gold'. Burning fossil fuels also releases CO₂ and pollutants, linking this topic to the pollution one. Because fossil fuels are limited and polluting, the syllabus pushes alternative/clean energy: solar, wind, hydro (water), tidal, geothermal and bio-gas. Students should learn to conserve fuel — the PCRA-style tips (switch off engines at red lights, maintain correct tyre pressure, use public transport). Pedagogy and misconceptions: children commonly think fossil fuels 'will never finish' or that they form quickly; correct this with the millions-of-years timescale and a discussion of why conservation matters. A good lesson contrasts a renewable and a non-renewable source and asks students to classify everyday energy uses. How it is tested: classify a given resource as renewable or non-renewable, identify the three fossil fuels, recall how/why they are exhaustible, name products of petroleum refining, and pick a conservation measure or a sound teaching strategy.

✅ Solved examples

1. Coal, petroleum and natural gas are grouped together as:
Fossil fuels — and they are non-renewable (exhaustible) because they form from buried organisms over millions of years but are used up far faster.
2. Which of the following is a renewable source of energy: coal, petroleum, or sunlight?
Sunlight (solar energy). It is replenished continuously by nature, unlike coal and petroleum, which are exhaustible fossil fuels.
3. Petrol, diesel, kerosene and LPG are all obtained from petroleum by:
Fractional distillation (refining) in a petroleum refinery, which separates crude oil into useful fractions. Petroleum is often called “black gold”.
4. A teacher wants Class VIII students to understand why we must save fossil fuels. The most accurate point to stress is that fossil fuels:
Take millions of years to form but are being consumed very quickly, so they are exhaustible and will run out — hence the need to conserve and shift to renewables.

✏️ Practice — try these, take hints as needed

1. Are coal and petroleum renewable or non-renewable resources?
They form over millions of years.
They will run out.
Non-renewable (exhaustible)
2. Name any one renewable source of energy other than the Sun.
Inexhaustible and clean.
Think of moving air or moving water.
Wind (or water/hydro, biomass, tidal, geothermal)
3. The slow conversion of dead vegetation into coal over millions of years is called:
A carbon-rich process.
Begins with the word “carbon”.
Carbonisation
4. Switching off a vehicle engine at a red light is an example of:
It saves petrol/diesel.
A conservation habit (PCRA-style tip).
Fuel conservation

📝 Topic test — 8 questions

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