Class 8 Science Chapter 3 Practice Question Answers - Coal and Petroleum

Q1: Name some renewable sources of energy.
Ans: Water, wind, solar.

Q2: Give some examples of fossil fuels.
Ans: Coal, petroleum, natural gas.

Q3: Name the elements present in coal.
Ans: Carbon, oxygen and sulphur.

Q4: Which are the two main techniques of mining?
Ans: Surface mining and underground mining.

Q5: List four varieties of coal.
Ans: Peat, lignite, bituminous, anthracite.

Q6: Name the process of conversion of wood into coal.
Ans: Carbonisation

Q7: Mention the temperature at which destructive distillation is done.
Ans: 1000°C

Q8: When the crude oil is referred to be ‘sweet’?
Ans: If the sulphur content is low.

Q9: Name the process of conversion of kerogen into gaseous hydrocarbons.
Ans: Catagenesis

Q10: Name the country which is the leading producer of petroleum.
Ans: Saudi Arabia

Q11: Resources which get replenished by natural processes in a certain period of time is called ___________.
Ans: renewable resources

Q12: ___________ is a mixture of various constituents such as lubricating oil, paraffin wax, etc.
Ans: Petroleum

Q13: All the things that are required to fulfil one’s need are called ___________.
Ans: resources

Q14: Which of the following is a renewable source of energy?
(a) Coal
(b) Petroleum
(c) Water
(d) Natural gas
Ans: (c)
Explanation: Water, in the context of hydropower, is a renewable source of energy because it comes from the water cycle (evaporation, condensation, and precipitation) and is continuously replenished by nature.

Q15: Which of the following is a non-renewable source of energy?
(a) Water
(b) Coal
(c) Soil
(d) Sun
Ans: (b)
Explanation: Coal is a non-renewable source of energy because it is formed from the remains of plants that lived millions of years ago and takes a very long time to replenish. Once coal deposits are used up, they cannot be easily replaced within a human lifetime.

Q16: Plastic is a
(a) natural material
(b) man-made material
(c) both (a) & (b)
(d) none of these
Ans: (b)
Explanation: Plastic is a man-made (synthetic) material derived from petrochemicals, which are obtained from petroleum. It is not a natural material that occurs in nature but is produced through industrial processes.

Q17: Fossil fuels are
(a) coal
(b) petroleum
(c) natural gas
(d) all of these
Ans: (d)
Explanation: Fossil fuels include coal, petroleum, and natural gas. They are formed from the remains of ancient plants and organisms that were subjected to heat and pressure over millions of years. These fuels are considered non-renewable because their formation takes geological timescales and they are being consumed much faster than they can be naturally replaced.

Q18: The word ‘coal’ is derived from the old English term
(a) col
(b) coke
(c) coco
(d) none of these
Ans: (a)
Explanation: The word "coal" is derived from the Old English term "col," which referred to charcoal or a piece of burnt wood. Over time, this term came to represent the solid carbon-rich material that we now know as coal.

Value-Based Questions
Q19: Radhey prefers to go to school by pooling car. On other occasions he like to opt for public transport rather than private transport. For short distances, he walks or uses bicycle.

1. What are the benefits of carpooling?
2. Which mean of transport do you think is best for short distances?
3. How on our end we can reduce the consumption of fossil fuels?
4. What values of Radhey are shown here?

Ans: 1.

• Cost effective
• Reduces pollution
• Reduces traffic on roads
• Saves fossil fuels

2. Bicycle

3.

• By reducing use of plastics as these are products of fossil fuels.
• By consuming electrical energy judiciously as most of the electricity comes from burning coal.
• By carpooling. As car uses petrol or diesel—a form of fossil fuel.
• Switching engine off at red lights.

4. Radhey is eco-friendly, environmentally conscious and works judiciously.

Q20: There was an essay-writing competition on ‘How to Reduce your Carbon Footprint’ in Satish’s school. Satish enquired his best on this topic to his elders and searched internet. He got the first prize in the competition.

1. What do you understand by the term ‘Carbon Footprint’?
2. Suggest ways to reduce your carbon footprint.
3. What values of Satish are shown here?

Ans: 1. The total amount of greenhouse gases produced by an individual, organisation or event is known as ‘Carbon Footprint’.
2.

• Follow 3R’s, i.e., – reduce, reuse and recycle.
• Use public transport and carpool.
• Avoid traffic.
• Plant trees.
• Use energy efficient appliances.

3. Satish is inquisitive, intelligent, hard working and sincere boy.