NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy

NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy Solutions to each chapter is provided in the list so that you can easily browse throughout different chapters NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy Notes and select need one. NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy Question Answers Download PDF. NIOS Study Material of Class 12 Environmental Science Paper Code 333.

NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy

Also, you can read the NIOS book online in these sections Solutions by Expert Teachers as per National Institute of Open Schooling (NIOS) Book guidelines. These solutions are part of NIOS All Subject Solutions. Here we have given NIOS Class 12 Environmental Science Chapter 33 Non – Renewable Sources of Energy Solutions, NIOS Senior Secondary Course Environmental Science Solutions for All Chapter, You can practice these here.

Non – Renewable Sources of Energy

Chapter: 33

Module 8 B: Energy and Environment

Textual Question Answer

INTEXT QUESTIONS 28.1

1. Mention the method of coal formation.

Ans: Plant material of swamps died and accumulated under water many centuries ago called peat. Sediments of sand and soil were deposited over the peat. The weight of sediments and heat from the earth change peat into soft coal (bituminous coal) to hard coal (anthracite). 

2. State the major uses of coal.

Ans: Coal is used as a fuel for domestic use. It is used in locomotive engines and various types of furnaces in the industries. It is used as a fuel in thermal power plants for generation of electricity. 

INTEXT QUESTIONS 28.2 

1. Which are the major fractions obtained from the distillation process of crude oil?

Ans: The products of fractions obtained from crude oil distillation are gases, gasoline (petrol), aviation fuel, kerosene, diesel oil, naphtha, grease and asphalt. 

2. What is the composition of conventional natural gas? Mention any one of its advantages as fuel?

Ans: Natural gas is a mixture of methane, with small amounts of heavier hydrocarbon such as ethane and butane. Advantages of natural gas are : a) It is used directly for cooking purposes at home, (b) It burns with smokeless and does not produce any poisonous gases on burning. 

INTEXT QUESTIONS 28.3 

1. What is meant by radioactive pollution?

Ans: Radioactive pollution is caused when radioactive substances (like uranium, plutonium, nuclear waste) are released into the environment. They emit harmful ionizing radiations that contaminate air, water, and soil, causing long-lasting health hazards such as cancer, genetic mutations, and ecological damage.

2. Distinguish between nuclear fission and nuclear fusion reactions.

Ans: Nuclear fission occurs because atoms of radioactive mineral contains nuclei that are unstable and break or split apart releasing energy. Nuclear fusion involves uniting two small atoms to form a large atom with the release of enormous amount of energy. 

3. What advantage does nuclear material has as energy source over coal and oil?

Ans: The advantage of nuclear material for energy generation is that produces very little pollution, it requires less mining as nuclear fuel is a concentrated form of energy and cost of transportation of nuclear fuel is lower than that for an equivalent amount of coal. 

TERMINAL EXERCISE

1. What actions can you take at a personal level to reduce consumption of fossil fuels? 

Ans: (i) Reduce the use of fossil fuels like coal, petroleum, etc.

(ii) Use renewable sources like solar energy, hydroelectric energy. 

(iii) Use electric vehicles. 

(iv) Use hydrogen as a fuel.

(v) Promote cycling.

2. How were fossils fuels formed? 

Ans: Fossil fuels were formed millions of years ago from the buried remains of plants (coal) and marine organisms like plankton (oil and natural gas). Under high pressure and temperature, and in absence of oxygen, these remains were transformed into coal, petroleum, and natural gas over geological time.

3. Discuss advantages and disadvantages of nuclear energy. 

Ans: Advantages of nuclear energy:

(i) A very small quantity of radioactive minerals can generate large amounts of energy.

(ii) It provides an alternative to fossil fuels, helping reduce dependence on coal, oil, and gas.

(iii) Produces very little air pollution, as no greenhouse gases or smoke are emitted during operation.

(iv) Once established, nuclear power plants can generate electricity at a relatively low running cost.

Disadvantages of nuclear energy:

(i) Availability of uranium and other radioactive ores is finite and limited.

(ii) Improper disposal of nuclear waste can cause long-lasting radioactive pollution.

(iii) Exposure to radiation can cause serious health hazards such as cancer and genetic disorders.

(iv) Nuclear power plants have a very high initial cost and require advanced safety systems.

4. Speculate which one of the fossil fuel will run out first. 

Ans: Based on current rates of production and requirement of the fuel, we can say that petroleum products like petrol and diesel are the fossil fuels that are going to run out first.

5. Discuss the importance of energy consumption to the society. What major concerns does it basis? 

Ans: All living organisms require energy for their metabolic activities. Living organisms obtain this energy required by them from food and are in the form of a chemical compound adenosine-triphosphate (ATP). This compound is synthesized mainly during the oxidation of food which occurs during cellular respiration.

(i) Apart from the energy required for one’s body processes, humans need energy for carrying out various kinds of activities. 

(ii) Heat or electrical energy is required for cooking and heating. Electricity is required for lighting bulbs and tube lights, running fans, coolers, and air conditioners.

(iii) Fuel such as petrol or diesel or compressed natural gas (CNG) is required in vehicles for transporting human beings and goods from one place to another. 

(iv) Energy (electricity) is required for pumping water up the multi-storied buildings. 

(v) Energy is required for the various industrial processes that ultimately result in the manufacture of different kinds of goods. 

(vi) Energy is required in agriculture, for irrigation, tractors and other farm machines, spraying pesticides.

(vii) Energy is required in power generation, e.g. rotating the turbines in hydro-electrical power generations.

6. Describe the pros and cons of the following types of fossil fuel. 

(i) Coal.

Ans: 

Pros	Cons
(a) Cheap and abundant in many countries	(a) Non-renewable, finite, limited
(b) Provides continuous and reliable power supply	(b) Causes severe air pollution (SO₂, CO₂, particulate matter)
(c) Supports many industries like steel and cement	(c) Contributes heavily to greenhouse gas emissions and global warming

(ii) Oil.

Ans: 

Pros	Cons
(a) Easily available and widely used	(a) Non-renewable, limited, finite
(b) High energy density, portable	(b) Causes pollution (air, water, soil)
(c) Essential for transport and petrochemical industry	(c) Risk of oil spills, which harm marine ecosystems

(iii) Natural gas.

Ans: 

Pros	Cons
(a) Cleaner and more environmentally friendly than coal or oil (low CO₂ and SO₂ emissions)	(a) Still a non-renewable resource
(b) Supplied directly to homes and industries via pipelines, reducing storage/transport costs	(b) Storage and transport under high pressure make it explosive and risky
(c) Flexible for power generation and cooking	(c) Methane leaks during extraction contribute to climate change

7. Describe the environmental degradation caused by the use of fossil fuel in 20th century.

Ans: The heavy dependence on fossil fuels in the 20th century caused serious environmental damage, such as:

(i) Natural gas leaks from pipelines, storage tanks, and distribution networks led to accidental explosions and fires.

(ii) Land subsidence: Oil and gas extraction caused the ground to sink (e.g., in Long Beach Harbor, Los Angeles, where the land sank by nearly 9 meters).

(iii) Brine contamination: For every barrel of oil, up to 10 barrels of brine were extracted, often polluting freshwater aquifers.

(iv) Marine pollution: Oil spills and natural seepage contaminated oceans, severely harming aquatic ecosystems.

(v) Damage to biodiversity: Oil spills killed aquatic plants, fish, and seabirds.

(vi) Air pollution: Burning coal, oil, and gas released SO₂, NOₓ, CO₂, and particulate matter, leading to smog, acid rain, and global warming.

8. Explain fusion and fission and differentiate them.

Ans: 

Nuclear Fission	Nuclear Fusion
The process by which the nucleus of a heavy atom of Uranium-235 or Plutonium-239 splits into smaller fragments releasing an enormous amount of energy.	The process by which small nuclei like isotopes of hydrogen namely deuterium and tritium join together to form heavier nuclei, releasing vast amounts of energy.
This happens inside a nuclear reactor at a nuclear power station.	This happens all the time in the Sun. It also happens when the most powerful nuclear weapon, a fusion bomb or hydrogen bomb, explodes.

9. Give your view on “Nuclear power and energy source”.

Ans: Nuclear energy is the energy of the nucleus of atoms. Radioactive minerals are used to generate nuclear energy through high technological methods. Radioactive minerals used for generating energy are a good alternative to fossil fuels. Similar to other minerals, the availability of ore of radioactive material is finite and limited. That is, nuclear energy is also a non-renewable resource. However, a very small quantity of radioactive minerals can generate large amounts of energy.