NIOS Class 12 Environmental Science Chapter 32 Importance of Energy In Society

NIOS Class 12 Environmental Science Chapter 32 Importance of Energy In Society Solutions to each chapter is provided in the list so that you can easily browse throughout different chapters NIOS Class 12 Environmental Science Chapter 32 Importance of Energy In Society Notes and select need one. NIOS Class 12 Environmental Science Chapter 32 Importance of Energy In Society Question Answers Download PDF. NIOS Study Material of Class 12 Environmental Science Paper Code 333.

NIOS Class 12 Environmental Science Chapter 32 Importance of Energy In Society

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 32 Importance of Energy In Society Solutions, NIOS Senior Secondary Course Environmental Science Solutions for All Chapter, You can practice these here.

Importance of Energy In Society

Chapter: 32

Module 8 B: Energy and Environment

Textual Question Answer

INTEXT QUESTIONS 27.1

1. How would you define energy?

Ans: Energy is the capacity to do work. 

2. What is a gram calorie?

Ans: It is the amount of heat required to raise the temperature of one gram of water through one degree centigrade from 14.50 to 15.50C. 

3. What is the SI unit of energy?

Ans: SI unit of energy is Joule (J). It is the work done when a force of one Newton displaces the point by one metre. 

4. State the First and the Second law of thermodynamics.

Ans: First law: energy can neither be created nor destroyed but can only change from one form to another.

Second law states that in every transformation, some energy is always lost in the form of heat. 

INTEXT QUESTIONS 27.2 

1. Define the terms renewable energy sources and non-renewable energy sources.

Ans: Energy that comes from sources whose supplies are inexhaustible and also the energy sources are generative or can be renewed. Energy resources that have limited amount of stocks available and the energy resources cannot be recreated in a short period of time. 

2. What are the various ways can solar energy be used?

Ans: Solar energy can be used in a variety of ways like to heat up homes, heat water (as solar cooker to prepare food). And produce electricity. 

3. List the various sources of renewable and non-renewable energy sources.

Ans: Renewable energy sources – Solar, wind, hydropower, geothermal, ocean, thermal energy, biomass, hydrogen. Non-renewable energy sources – Coal, gas, oil or petroleum. 

4. Why is hydrogen known as a clean energy source?

Ans: Hydrogen produces clean energy and pure water without causing any pollution. 

5. How is coal formed in nature?

Ans: Coal is formed from the remains of plants that lived millions of years ago in swampy areas. These remains were buried under sediments, and over millions of years, heat and pressure transformed them into coal.

TERMINAL EXERCISE

1. What do you understand by bio-energy? Describe the various types and ways of using biomass energy. 

Ans: When electricity and gas are generated from natural resources, it is known as bioenergy. Electricity is generated from gas, wood, anything that is natural resources. In bioenergy or biomass energy is obtained from organic matter. These biomass fuels are a renewable source of energy. It is a clean and low-cost fuel. Ethanol is a liquid fuel that is produced from biomass.

2. Define first and second law of thermodynamics. 

Ans: The first law of thermodynamics states about conservation of energy. It says that the form of energy can be changed. It cannot be destroyed or created.

The second law of thermodynamics states energy transformation, which says that some form of energy is lost in the form of heat which remains unavailable and cannot be used.

3. Prepare a list of renewable and non renewable energy resources. 

Ans: The renewable source of energy is solar energy, wind energy, biomass or bioenergy, bío-diesel, hydropower, wave energy, ocean thermal energy, geothermal energy, fuel cell technology.

The non-renewable source of energy is oil, petroleum, natural gas, coal, nuclear energy.

4. What is a fuel cell? Which fuel is used to propel rockets? 

Ans: The device that directly converts hydrogen into electricity is the fuel cell. Hydrogen is a colourless, odourless gas. Hydrogen is a clean fuel. In NASA’s space shuttle program hydrogen has been used as a fuel since 1970 to propel a rocket. It provides heat, electricity, and drinking water for astronauts. It produces pollution-free energy.

5. What type of conditions necessary for biogas generation? 

Ans: Biogas generation requires anaerobic conditions (absence of oxygen), optimum temperature around 30–40°C, and sufficient moisture. It needs organic feedstock such as cattle dung, human excreta, agricultural residue, or other biodegradable wastes. These conditions allow anaerobic microbes to decompose the material and produce methane-rich biogas.

6. What is the average composition of biogas? 

Ans: The average composition of biogas is about 55–75% methane (CH₄), 25–40% carbon dioxide (CO₂), and small amounts of hydrogen, nitrogen, and hydrogen sulphide (H₂S). It is an inflammable, clean, low-cost fuel used for cooking, lighting, and electricity generation. The leftover slurry is a good organic manure for agriculture.

7. Why hydrogen is considered as a clean energy source? 

Ans: Hydrogen is a clean energy source as its Conversion into electricity does not produce any kind of pollution. Fuel cell technology converts hydrogen into electricity. Hydrogen is used as a fuel in NASA to propel a rocket. In the coming future, hydrogen could easily substitute another sOurce of energy.

8. What is the ultimate source of energy in coal and petroleum? 

Ans: The phytoplankton and plants decay under complex processes and form coal and petroleum. Coal primarily consists of carbon but also contains some traces of sulfur. It is formed from plants and animals which grew millions of years ago. 40% of commercial energy in the world is provided by petroleum.

9. Describe the process of coal and petroleum formation. 

Ans: From dead plants and animals, the formation of coal and petroleum occurs. Plants and animals, phytoplankton and zooplankton, remain buried for millions of years ago. Under the constant high pressure of heat, they get converted. As oxygen is absent over there, it will not rot completely. Coal and petroleum are one of the most vital resources. 

10. State the reasons for increasing emphasis on developing renewable sources of energy.

Ans: Renewable source of energy is required more due to increasing population. There is more pressure on developing renewable sources of energy as this type of energy can be renewed again and again. Due to the ever-increasing population day by day, the natural resources are getting Used in a very fast way. Hence to replenish the resources, there is pressure to develop a renewable source of energy.

11. Which type of power or energy causes no pollution?

Ans: Renewable and clean energy sources such as solar, wind, hydropower, geothermal, tidal, and hydrogen energy cause no pollution. Hydrogen in particular is considered a very clean fuel, as its use produces only water as a by-product and no harmful emissions.