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Natural Resources and Energy - Fossil Fuels: Petroleum and Coal

Grade 5CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Natural Resources: These are substances found in nature that humans use. They are divided into Renewable (e.g., Solar, Wind) and Non-renewable (e.g., Coal, Petroleum) resources.

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Fossil Fuels: Formed from the remains of dead plants and animals buried deep inside the earth millions of years ago. They are non-renewable because they take millions of years to form.

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Coal: A hard, black combustible mineral. It is formed through a process called carbonization, where buried vegetation is converted into coal under high pressure and temperature. It primarily consists of Carbon (CC).

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Petroleum: Also known as 'Black Gold'. It is a dark, oily liquid found between layers of rocks in the earth. It is formed from the remains of tiny sea organisms buried under sand and silt.

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Fractional Distillation: The process used to separate the various constituents of petroleum, such as Petrol, Diesel, Kerosene, and Paraffin wax, based on their different boiling points.

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Natural Gas: Often found along with petroleum. It is stored under high pressure as Compressed Natural Gas (CNG). Its main component is Methane (CH4CH_4).

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Environmental Impact: Burning fossil fuels releases greenhouse gases like Carbon Dioxide (CO2CO_2), which contributes to global warming.

📐Formulae

Dead Vegetation+High Temperature+High Pressure→Millions of YearsCoal\text{Dead Vegetation} + \text{High Temperature} + \text{High Pressure} \xrightarrow{\text{Millions of Years}} \text{Coal}

Methane (Natural Gas)=CH4\text{Methane (Natural Gas)} = CH_4

Carbon Dioxide=CO2\text{Carbon Dioxide} = CO_2

Water=H2O\text{Water} = H_2O

💡Examples

Problem 1:

Explain why Fossil Fuels are considered 'exhaustible' resources using the concept of time.

Solution:

Fossil fuels take millions of years (>106> 10^6 years) to form from organic matter, but they are being consumed by humans at a very rapid rate.

Explanation:

Because the rate of consumption is much higher than the rate of formation, these resources will eventually run out, making them non-renewable or exhaustible.

Problem 2:

Which is a cleaner fuel for transport: Petrol or CNG? Why?

Solution:

CNG is a cleaner fuel.

Explanation:

When CNG (mostly CH4CH_4) burns, it produces fewer harmful pollutants and less CO2CO_2 compared to petrol or diesel, making it more environment-friendly.

Problem 3:

Name the process that turns dead plants into coal.

Solution:

Carbonization.

Explanation:

Under the conditions of high pressure and high temperature, the slow process of conversion of dead vegetation into coal is called carbonization, as coal contains mainly Carbon (CC).