Fossil Fuels

and

The Carbon Cycle

The Carbon Cycle

Carbon Cycle

• The Carbon Cycle is a model describing how carbon molecules move between the living and nonliving world.

Characters of the Carbon Cycle• Producer – an organism that

makes its own food• Consumer – an organism that

obtains energy by eating other organisms

• Decomposer – breaks down the wastes and dead bodies of other organisms

Producers

• Producers take in carbon dioxide from the atmosphere during photosynthesis.

• They use carbon to make food molecules – carbohydrates.

• They release oxygen and water during respiration.

Consumers

• When consumers eat producers, they take in the carbohydrates.

• When consumers break down these carbohydrates, they release carbon dioxide and water during respiration.

Decomposers

• Once the consumers release the waste decomposers, such as bacteria, break down the wastes and dead bodies of other organisms.

Fossil Fuels

• Fossil Fuels are burned for energy by combustion and release carbon dioxide and other greenhouse gases.

Review

• Describe the steps of the Carbon Cycle.

• Animals and burned fossil fuels release carbon dioxide.

• Plants use carbon dioxide for photosynthesis to make energy for the plant.

• Plants can be consumed by animals for energy.

• Plants and animals die.

• Animals release waste and both are decomposed by bacteria.

• Fossil fuels can be made from decomposed material and used for energy through combustion.

Bellringer

• In the 1800’s and early 1900’s, how was coal most commonly used?

• In the 1800’s and early 1900’s coal was commonly used to power trains.

Objectives

• Describe how humans use natural resources.

• Describe what energy resources are.

• Identify three different forms of fossil fuels.

• Explain how fossil fuels form.

• Describe how fossil fuels are found and obtained.

Earth’s Resources

• A natural resource is any natural material that is used by humans, such as water, petroleum, minerals, forests and animals.

Renewable resource

• A renewable resource is a natural resource that can be replaced at the same rate at which it is used.

Nonrenewable resource

• Not all of Earth’s natural resources are renewable.

• A nonrenewable resource is a resource that forms at a rate that is much slower than the rate at which it is consumed.

Conservation

• Most of the natural resources that provide us energy are nonrenewable resources. If we don’t limit our use of energy now, the resources may not be available in the future.

Energy Resources

• Energy resources are natural resources that humans use to generate energy.

• Most of the energy we use comes from a group of natural resources called fossil fuels.

Fossil Fuels

• A fossil fuel is a nonrenewable energy resource formed from the remains of plants and animals that lived long ago.

• Petroleum, coal, and natural gas are examples of fossil fuels.

• Energy is released from fossil fuels when they are burned.

Types of Fossil Fuels

• All living things are made up of the element carbon.

• Since fossil fuels are formed from the remains of plants and animals, all fossil fuels are made of carbon, too.

• Different fossil fuels have different forms. Fossil fuels may exist as liquids, gases, or solids.

Liquid Fossil Fuels

• Petroleum A liquid mixture of complex hydrocarbon compounds is called petroleum.

• Petroleum is also commonly known as crude oil.

• More than 40% of the world’s energy comes from petroleum products.

Gaseous Fossil Fuels

• Natural Gas A gaseous mixture of hydrocarbons is called natural gas.

• Most natural gas is used for heating, but it is also used for generating electrical energy.

• Methane, CH4, is the main component of natural gas.

• Other components, such as butane and propane, can be separated from natural gas, too.

Solid Fossil Fuels

• The solid fossil fuel that humans use most is coal.

• It was once the major source of energy in the United States.

Review

• Describe natural energy resources.

• Identify three different forms of fossil fuels.

Bellringer

• How are natural gas and petroleum removed from Earth?

• Natural gas and petroleum are removed from Earth by drilling wells into rock that contains these resources.

How Do Fossil Fuels Form?

• Petroleum and natural gas form mainly from the remains of microscopic sea organisms.

• Through physical and chemical changes over millions of years and under the pressure of over-laying rocks and sediments, the remains become petroleum and gas.

Coal Formation

• Coal forms differently from the way petroleum and natural gas form.

• Coal forms underground from decayed swamp plants over millions of years. When the plants die, they sink to the bottom of the swamp, beginning the process of coal formation.

Where Are Fossil Fuels Found?

• Fossil fuels are found in many parts of the world. The United States has large reserves of petroleum, natural gas, and coal.

How Do We Obtain Fossil Fuels?

• People obtain coal either by mining deep beneath Earth’s surface or by surface mining.

• Surface mining, also known as strip mining, is the process by which soil and rock are stripped from the Earth’s surface to expose the underlying coal that is to be mined.

Review

• Explain how fossil fuels form.

• Describe how fossil fuels are found and obtained.