Summary
Chapter 11 of the Class 6 Science NCERT textbook (Curiosity), "Nature's Treasures", explores the key natural resources — air, water, solar energy, forests, soil, rocks, minerals, and fossil fuels — and teaches students how to classify, conserve, and use them responsibly.
- Air and water as life-givers — Air is a mixture of gases — nitrogen (78%), oxygen (21%) and others — and we cannot survive without oxygen for even minutes. Water covers about two-thirds of Earth, but most is salty ocean, making freshwater limited and precious.
- Solar energy and forests — The Sun is Earth's main energy source; plants use its light to make food that feeds all living beings, and solar panels and cookers tap it directly. Forests provide food, shelter and biodiversity, while their roots prevent soil erosion.
- Soil, rocks and fossil fuels — Soil and rocks form slowly over thousands to millions of years. Fossil fuels like petroleum, coal and natural gas take millions of years to form from buried remains, which is why they are treated as non-renewable.
- Renewable vs non-renewable, and conservation — Renewable resources such as air, water and forests replenish in a reasonable time; non-renewable ones like fossil fuels and minerals do not. India's traditions of conservation include rainwater harvesting, the Chipko movement and Van Mahotsav.
Key points & formulas
- 01Air is a mixture of gases: nitrogen (78%), oxygen (21%), and argon, carbon dioxide and other gases (1%).
- 02We can survive without food or water for a few days but cannot survive without oxygen for even a few minutes.
- 03Moving air is called wind; windmills use wind energy to run flour mills, pump water, and generate electricity.
- 04Water covers about two-thirds of Earth's surface; most is saline ocean water not fit for use — freshwater is limited and precious.
- 05Rainwater harvesting (e.g., Bawadi stepwells in Rajasthan, Vav in Gujarat) is an age-old Indian practice to conserve water.
- 06The Sun is the main source of energy on Earth; plants use sunlight to make food, and this energy passes through all living beings.
- 07Solar panels capture the Sun's energy to produce electricity; solar cookers and solar water heaters are other direct uses.
- 08Forests are large areas with dense plant growth that provide food, shelter, and biodiversity; roots prevent soil erosion and fallen leaves enrich soil nutrients.
- 09Fossil fuels (petroleum, natural gas, coal) take millions of years to form from buried remains of microorganisms and plants — they are non-renewable.
- 10Renewable resources (air, water, forests) get replenished within a reasonable period; non-renewable resources (coal, petroleum, natural gas, minerals, soil, rocks) do not.
- 11The Chipko movement began in the early 1970s in Uttarakhand, where local women hugged trees to protect them from being felled.
- 12Van Mahotsav is a week-long forest festival celebrated in July across India to increase green cover.
Frequently asked questions
01What is Chapter 11 'Nature's Treasures' about in Class 6 Science?
Chapter 11 covers the major natural resources — air, water, solar energy, forests, soil, rocks, minerals, and fossil fuels. It explains their importance for all life on Earth, how they are formed, and how students can classify and conserve them as renewable or non-renewable resources.
02What is the composition of air according to Chapter 11?
Air is a mixture of gases: nitrogen makes up 78%, oxygen makes up 21%, and the remaining 1% is argon, carbon dioxide and other gases. Nitrogen is the most abundant gas in air.
03What are renewable and non-renewable resources with examples from this chapter?
Renewable resources get renewed, replenished or restored within a reasonable period — examples from the chapter are air, water, and forests. Non-renewable resources are in limited quantities and do not get replenished in a reasonable period — examples are fossil fuels (coal, petroleum, natural gas), minerals, soil, and rocks.
04How are fossil fuels formed and why are they non-renewable?
Fossil fuels (petroleum, natural gas, coal) are formed from the remains of microorganisms and plants that got buried deep inside the earth and were converted over millions of years. Because they take millions of years to form and are found in limited quantities, they are classified as non-renewable resources.
05What is rainwater harvesting and what are Bawadi and Vav?
Rainwater harvesting means collecting and storing rainwater in large quantities for later use. Bawadi (in Rajasthan) and Vav (in Gujarat) are traditional stepwells used for water harvesting. They store not only rainwater but also water seeping from nearby lakes, ponds, and rivers through stone-lined trench walls.
06Why is the Sun called the main source of energy on Earth?
Plants use sunlight to prepare food. Animals eat plants and grow. We get food from both plants and animals. Solar panels, solar cookers, and solar water heaters also use the Sun's energy directly. The entire food and energy cycle on Earth is possible due to the Sun.
07What is the Chipko movement and where did it start?
The Chipko movement was a forest protection movement where local women encircled and hugged trees to protect them from being felled. It started in the early 1970s in Uttarakhand, which was previously part of Uttar Pradesh.
08What is Van Mahotsav and when is it celebrated?
Van Mahotsav is a week-long forest festival celebrated across India during the month of July. New plants and trees are planted, and awareness about respecting and protecting forests is raised to increase the country's green cover.
09How is soil formed and why is it considered a non-renewable resource?
Soil is formed by the disintegration (breaking apart) of rocks by the actions of the Sun, water, and living organisms over thousands of years. Because soil formation takes such a very long time, it is classified as a non-renewable resource.
10What are the differences between natural resources and human-made resources?
Natural resources are those we get from nature, such as air, water, sunlight, forests, soil, rocks, minerals, and fossil fuels. Human-made resources are created by human beings to meet their needs, such as electric bulbs, furniture, solar panels, and bicycles.
11Why is there a water shortage in many parts of India even though water covers two-thirds of Earth?
Most water on Earth is in oceans and seas and is saline (salty), making it unfit for domestic, agricultural, and industrial use. Freshwater in ice sheets and underground is difficult to access. Only a very small fraction in ponds, rivers, lakes, and wells is easily accessible, leading to water shortages.
12Is the Class 6 Science Chapter 11 PDF free to download — do I need to sign up?
Yes, the NCERT Curiosity Class 6 Science Chapter 11 PDF is available for free on our app and website — no sign-up or account required.
More chapters in Curiosity
Read Chapter 11 of Curiosity, the Class 6 Science NCERT textbook (2026-27 edition), online for free: the complete chapter as published by NCERT with every diagram, solved example and exercise, with step-by-step solutions, answers and revision notes. Open the NCERT PDF above, or browse all NCERT Class 6 textbooks.
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