Comprehensive Notes on Natural Resources, Fossil Fuels, and Energy Conservation

Natural Resources and Their Uses

Ways We Use Natural Resources

• Rocks and soil are used for construction (houses, roads, dams).
• Metals (iron, aluminum, copper) are used for buildings, bridges, machines, vehicles, airplanes, utensils, and household items.
• Fuels (coal, petroleum, natural gas) are used for cooking, running vehicles and machines, and producing electricity.

Classification of Materials

• Natural materials: Found on Earth and support life (e.g., air, water, soil, minerals, plants, animals).
• Human-made materials: Created by humans.

Definition of Natural Resources

• Natural resources are materials found on Earth that support life and satisfy the needs of living organisms.
• Living natural resources: Plants and animals.
• Non-living natural resources: Air, water, soil, and minerals.

Sources of Natural Resources

• Solid parts of the Earth's crust.
• Water bodies: Seas, rivers, and lakes.
• Atmosphere: Gases surrounding the Earth.

Renewable and Non-Renewable Resources

Renewable Resources

• Resources that either never run out or are replaced within a reasonable time through natural processes.
• Examples:
  • Sunlight: Expected to last for another 5 billion years.
  • Oxygen: Replaced by plants during photosynthesis.
• Most renewable resources can be exhausted if used faster than they are renewed or if their renewal process is disturbed.
  • Example: Groundwater is being used faster than it is renewed, leading to decreasing levels.

Non-Renewable Resources

• Resources that cannot be replaced within a reasonable time once used up (takes millions of years).
• Examples:
  • Fuels: Petroleum, natural gas, coal.
  • Topsoil: Takes hundreds of years to form.
• Some non-renewable resources, like metals, can be recycled and used again.

Conservation of Resources

Importance of Conservation

• All life on Earth depends on Earth's resources.
• Conservation is the wise and careful use of resources, avoiding waste and maintaining quality.

Reasons for Increased Focus on Conservation

• Increased world population: More people require more resources for basic needs.
• Increased human needs: Progress has led to increased energy demands and resource consumption per person.

Consequences of Resource Depletion

• Faster depletion of natural resources, leading to imbalances in nature.
• Environmental issues: Pollution of air, water, and soil; climate change; decline in animal and plant populations.
• Risk to survival if conservation is not practiced.

Fuels

Definition of Fuel

• Any substance that burns and gives off heat.
• A fuel is a substance used to produce heat at a reasonable cost.
• Fuels contain potential energy within their chemical bonds.
• When fuels are burned, energy is released as heat.
• Common fuels contain carbon.

Fossil Fuels

Formation of Fossil Fuels

• Coal, petroleum, and natural gas are formed from the remains of dead organisms over millions of years.
• Coal: Formed from dead plants.
• Petroleum and natural gas: Formed from dead sea animals.
• Energy in fossil fuels is indirectly derived from the sun.

Importance of Fossil Fuels

• Major source of energy today.
• Concentrated stores of energy that release heat and light when burned.
• Uses: Cooking, running engines (automobiles), generating electricity (powerhouses).

Coal

Formation of Coal

• Formed over millions of years from gradual decay and compression of buried ancient forests.
• Around 300 million years ago, dense forests in wetlands were covered with sand and mud.
• Subsequent layers of trees and sediment increased pressure and temperature.
• This process converted vegetation into coal, known as coalification.
• This period of coal formation is called the Carboniferous Age.

Composition of Coal

• Mainly carbon, with hydrogen, oxygen, nitrogen, and sulfur.

Varieties of Coal

• Anthracite: Up to 96% carbon (best quality).
• Bituminous coal: About 65% carbon.
• Lignite: About 38% carbon.

Uses of Coal

• Burning coal in air produces carbon dioxide: $C + O<em>2 \rightarrow CO</em>2$
• Used as a domestic and industrial fuel.
• Widely used in thermal power plants to produce electricity.

Coal Deposits in India

• Mainly found in Jharkhand, West Bengal, Odisha, Chhattisgarh, Madhya Pradesh, and Tamil Nadu.

Destructive Distillation of Coal

• Heating coal strongly to $1000^\circ C$ in the absence of air.
• Yields useful organic and inorganic products.
  • Coke: Residue is almost pure carbon, good fuel, used to reduce metal oxides like iron and zinc oxides.
  • Coal gas: Mixture of hydrogen, methane, carbon monoxide; used for cooking and lighting.
  • Coal tar: Thick viscous liquid used for road construction, contains carbon compounds used to make pesticides, explosives, synthetic fibers, perfumes, dyes and paints.
  • Ammonium compounds: Used for making nitrogenous fertilizers.

Petroleum

Occurrence and Composition

• Also known as crude oil, found trapped in underground rocks.
• A mixture of various hydrocarbons with differing numbers of carbon atoms (from 1 to over 100).
• Components are separated and used in various ways, primarily as fuel (petrol, diesel, kerosene).

Origin of Petroleum

• Formed over millions of years from dead sea organisms.
• Bodies settled on the seabed and were covered with sand and clay.
• Heat and pressure transformed the dead organisms into petroleum hydrocarbons.

Occurrence of Petroleum

• Often found with natural gas in large deposits deep inside Earth's crust.
• Obtained by drilling through Earth and impervious rock.
• First oil well in Pennsylvania, USA (1859).
• First oil in India in Makum, Assam (1867).
• Oil wells in Assam, Gujarat, Bombay High, and deltas of Godavari and Kaveri rivers.
• Crude oil is a black liquid, referred to as "black gold".

Refining of Petroleum

• Hydrocarbons in petroleum have different boiling points.
• As carbon atoms increase, boiling point increases.
• Fractional distillation separates components.
• Process carried out in a petroleum refinery.

Process:

• Crude oil is heated to $400^\circ C$ in a furnace.
• Vapors pass into a fractionating tower.
• Hydrocarbons with the highest boiling condense first.
• As vapor rises, hydrocarbons with lower boiling points condense at different heights.
• Hydrocarbons with 1-4 carbon atoms (gases) do not condense and escape from the top.

Important Fractions of Petroleum and Their Uses

Variations in Petroleum Composition

• Petroleum extracted from different wells varies in composition, density, and impurities (sulfur, lead, arsenic, arene).
• This can cause composition and boiling points of fractions to differ.

Additional Uses of Petroleum

• Chemicals from petroleum are used to make medicines, ointments, and cosmetics.
• Further fractional distillation yields chemicals for plastics, synthetic rubber, synthetic fibers, and explosives.

Natural Gas

Composition and Occurrence

• Found with petroleum in underground reservoirs.
• Chiefly methane, with butane and propane.
• Easily transported through pipes and cleaner fuel.
• Stored as compressed natural gas (CNG).

Uses of Natural Gas

• CNG is used for power generation.
• Supplied to homes and factories through pipes in some areas (e.g., Vadodara).
• Used as a non-polluting fuel for vehicles.
• Used in the manufacture of chemicals and fertilizers.

Natural Gas Deposits in India

• Tripura, Rajasthan, Maharashtra, and Krishna-Godavari delta.

Energy and Technological Development

Increasing Energy Needs

• Increase in population.
• New technologies require more energy to run factories and power gadgets.

Areas of Increased Energy Consumption

• Manufacturing goods in factories.
• Agriculture: Running tube-wells, tractors, and other machines.
• Food processing and storage in cold storage.
• Transportation.
• Increased use of electrical gadgets at home (refrigerators, air conditioners, washing machines).

Electricity as a Major Energy Source

• Tremendous surge in electrical energy use.
• Electrical energy is not a natural source and is produced through conventional and non-conventional methods.

Energy Crisis in India

• Supply of electrical energy is lower than requirements.
• Causes power cuts and limits the use of new technologies.
• Affects industrial production and development.
• Insufficient and unreliable electricity in villages affects irrigation and food production.

Preventing Energy Crisis

Judicious Use of Energy

• Avoid wasting energy and use energy-efficient methods.

Methods to Avoid Wasting Energy:

• Switching off lights and fans when not in use.
• Using air coolers, air conditioners, heaters, and geysers only when needed.
• Reducing flame while cooking.

Methods to Use Energy Efficiently:

• Using CFLs and LEDs instead of bulbs (LEDs are preferable to CFLs because CFLs contain toxic mercury).
• Using public transport instead of private vehicles; walking or cycling for small distances.
• Using pressure cookers for cooking.
• Using efficient smokeless chulhas instead of kerosene, coal, or wood.
• Reducing cooking time by soaking pulses and covering vessels.

Advantages of Judicious Energy Use

• Delays the energy crisis.
• Gives scientists time to develop efficient alternate energy sources.

Conservation of Fossil Fuels

• India imports most of its petroleum.
• Exhaustible resources like coal and petroleum will be finished soon if not managed properly.
• Use natural gas as a substitute.
• Use alternative energy sources such as solar, wind, and biomass.

Role of Biogas and Biotechnology

• Biogas is a cheap fuel for rural populations, produced from waste products.
• Effective use of biomass to derive many products of industrial and commercial has increased with the progress in biotechnology.

New Words

• Fractions: Components with different boiling points obtained during fractional distillation.
• Refining: The process of separating the fractions by fractional distillation.