Fossil Fuels IAN p 31 Textbook pp 104-111

Fuel Fossil Fuels A substance that provides energy, such as heat, light, motion, or electricity Result of a chemical change Energy-rich substances formed from the remains of living organisms These organisms lived hundreds of millions of years ago Heat and pressure changed remains of these organisms into other substances Coal, oil, natural gas

Hydrocarbons Burning fossil fuels Carbon and hydrogen atoms Make up fossil fuels When burned, atoms react and combine with oxygen = release heat and light Provides more energy per kilogram than other fuels 1 kg coal = 2x 1kg wood Oil and natural gas = 3x equal mass of wood

Coal 1800s-growing industries = huge energy needs; switched to coal 22% of fuel used in US, most used for electrical power plants Must be mined; dangerous work Most plentiful fossil fuel in US, provides a lot of energy Increases erosion, runoff= water pollution, much air pollution

Oil (Petroleum) Liquid fossil fuel Formed from remains of small animals, algae, other organisms in oceans and seas hundreds of millions of years ago Earth’s oil reserves took 500 million years to form > 1/3 of energy produced in the world Cars, airplanes, trains, ships, heat for homes Located in tiny holes in sandstone or limestone underground Crude oil = oil first pumped out of ground Refinery = factory that heats crude oil and separates it into fuels

Petrochemicals Compounds made from oil Used to make plastics, paints, medicines, and cosmetics

Natural Gas Mixture of methane and other gases Forms in same way as oil Less dense than oil, rises above oil deposits Transported by pipeline Also compresses into a liquid fuel (buses, trucks) Produces large amounts of energy, lower levels of many air pollutants, easy to transport Highly flammable, no odor (odor is added so we can detect a link)

Nonrenewable Resources Take hundreds of millions of years to form Limited Not replaceable in human lifetimes Fossil fuels Minerals Fresh water Uneven distribution: take special conditions to form US: uses ¼ of oil in world, has 2% of world’s oil supply

IAN p 30 – Oil and Natural Gas Formation Book 300-400 Million Years Ago 50-100 Million Years Ago Plankton die and fall to ocean floor Layers of sediment bury their remains Remains buried depr under sediment Bacteria decompose oceanic matter Pressure and temperature increase

IAN p 30 – Oil and Natural Gas Formation Book Today Greater pressure and temperature = thick, liquid oil and natural gas forms Oil and natural gas begin to rise through pores until they get trapped by impermeable rock Oil and natural gas are collected