What is Coal (fossil fuel)?

S4-SA2-0845

Grade Level:

Class 7

Space Technology, EVs, Climate Change, Biotechnology, HealthTech, Robotics, Chemistry, Physics

Definition

What is it?

Coal is a black or brownish-black rock that is a fossil fuel. It was formed over millions of years from dead plant matter buried deep underground, under immense heat and pressure. We burn coal mainly to produce energy.

Simple Example

Quick Example

Imagine your school bus uses diesel, which is also a fossil fuel. Just like diesel comes from crude oil formed long ago, coal is another type of fossil fuel that comes from ancient plants. We use it to generate electricity, much like how your phone needs electricity to charge.

Worked Example

Step-by-Step

Let's say a power plant needs 100 kg of coal to generate electricity for 50 homes for one day. If your town has 500 homes, how much coal is needed for one day?

Step 1: Find out how many groups of 50 homes are in your town. Total homes = 500, Homes per group = 50. Number of groups = 500 / 50 = 10 groups.
---Step 2: Each group of 50 homes needs 100 kg of coal. So, for 10 groups, multiply the coal needed per group by the number of groups. Coal needed = 100 kg/group * 10 groups.
---Step 3: Calculate the total coal needed. Coal needed = 1000 kg.

Answer: Your town would need 1000 kg (or 1 tonne) of coal for one day to power 500 homes.

Why It Matters

Understanding coal is crucial because it's a major energy source, impacting everything from the electricity powering your mobile charger to the manufacturing of goods. It connects to Climate Change due to emissions and inspires careers in renewable energy research or environmental engineering to find cleaner alternatives.

Common Mistakes

MISTAKE: Thinking coal is a renewable resource because we keep finding more of it. | CORRECTION: Coal is a non-renewable fossil fuel. It takes millions of years to form, so we use it up much faster than nature can create it.

MISTAKE: Believing all black rocks are coal. | CORRECTION: While coal is a black rock, not all black rocks are coal. Coal has specific properties, like being combustible and forming from ancient plant matter, unlike many other black rocks.

MISTAKE: Confusing coal with charcoal. | CORRECTION: Coal is a natural fossil fuel formed underground over millions of years. Charcoal is man-made by burning wood in low oxygen, often used for barbecues.

Practice Questions

Try It Yourself

QUESTION: Is coal a fossil fuel or a renewable energy source? | ANSWER: Coal is a fossil fuel.

QUESTION: Name two conditions necessary for the formation of coal from dead plant matter. | ANSWER: High heat and high pressure.

QUESTION: If a small village uses 200 kg of coal per week for heating, and there are 10 such villages in a district, how much coal is needed for the district in one month (assume 4 weeks in a month)? | ANSWER: 200 kg/village/week * 10 villages * 4 weeks/month = 8000 kg or 8 tonnes.

MCQ

Quick Quiz

Which of the following is NOT true about coal?

It is formed from dead plant matter.

It is a renewable resource.

It is used to generate electricity.

It is a fossil fuel.

The Correct Answer Is:

Coal is a non-renewable fossil fuel because it takes millions of years to form, and we consume it much faster than it can naturally replenish.

Real World Connection

In the Real World

In India, many power plants, like the ones you see near cities or hear about in news, use coal to generate the electricity that powers our homes, schools, and factories. This electricity charges your phone, runs the AC, and lights up your streetlights. Scientists and engineers are constantly working to make these processes more efficient or find cleaner alternatives to reduce pollution.

Key Vocabulary

Key Terms

FOSSIL FUEL: Fuels formed from the remains of ancient plants and animals over millions of years | COMBUSTIBLE: Capable of catching fire and burning | NON-RENEWABLE: A resource that cannot be easily replenished once used up | THERMAL POWER PLANT: A power station where heat energy is converted into electricity, often by burning coal | EMISSIONS: Gases or particles released into the air, especially by burning fuel

What's Next

What to Learn Next

Next, you can explore "What are Renewable Energy Sources?" This will help you understand alternatives to fossil fuels like coal and how we can power our future more sustainably, linking to important topics like Climate Change and cleaner technologies.