Fossil fuels

Question 1

• Recall the original energy source for the energy stored in fossil fuels

Answer 1

The energy in fossil fuels comes from the sun, which drives photosynthesis to change carbon dioxide and water into the molecular building blocks of ancient plants and animals.

Question 2

describe

• Describe the formation of fossil fuels

Answer 2

Fossil fuels are compound mixtures made of fossilized plant and animal remnants from millions of years ago. The creation of fossil fuels—either oil, natural gas, or coal—from these fossils is determined by the type of fossil, the amount of heat, and the amount of pressure.

Question 3

outline

• Outline methods for mining coal (surface, open-cut or underground) and natural gas in Australia

Answer 3

Surface Mining
If coal is less than 61 meters (200 feet) underground, it can be extracted through surface mining.
In surface mining, workers simply remove any overlying sediment, vegetation and rock.
Open-pit mining is used when coal is located deeper underground. A pit, sometimes called a borrow, is dug in an area. This pit becomes the open-pit mine, sometimes called a quarry.Open-pit mining is used when coal is located deeper underground. A pit, sometimes called a borrow, is dug in an area. This pit becomes the open-pit mine, sometimes called a quarry.

Natural gas is most commonly extracted by drilling vertically from the Earth’s surface. From a single vertical drill, the well is limited to the gas reserves it encounters. Natural gas wells can be drilled vertically and horizontally into natural gas-bearing formations. In conventional natural gas deposits, the natural gas generally flows easily up through wells to the surface.

Question 4

explain

• Explain why fossil fuels are non-renewable

Answer 4

they take billions of years to from naturally from the remains of ancient plants and animals. therefore it is non-renewable.

Question 5

explain

• Explain why we need to shift away from fossil fuels

Answer 5

there are many risk to fossil fuels which include, safety concerns, expenses, non renewable and the environment (carbon emmisions)

Question 6

describe

• Describe covalent bonding

Answer 6

Covalent bonding occurs when non-metal atoms interact. Non-metal atoms look to gain more electrons. They have two ways of achieving this:

1. getting electrons from a metal (ionic compound)
2. sharing electrons between non-metal atoms (covalent molecule)

Question 7

• Compare ionic, metallic and covalent bonding

Answer 7

Ionic bonds are formed when two atoms exchange electrons to create a positive and negative ion. Covalent bonds are formed when atoms share electrons to create a molecule. Metallic bonds are created when metal atoms lose their outermost electron to form positively charged ions. Metallic bonding is the electrostatic attraction between positive metal ions and delocalised electrons.

Question 8

• Recall that energy is released from fossil fuels through combustion reactions

Answer 8

Fossil fuels are used to produce energy; in the home they are burned to produce heat, in large power stations they are used to produce electricity and they are also used to power engines.

Question 9

Identify the products of combustion

Answer 9

During complete combustion, the reactant burns in excess (plentiful) oxygen and produces products such as carbon dioxide and water.

Question 10

• Write word equations to summarise combustion reactions

Answer 10

The word equation for the complete combustion of butane is:

butane + oxygen
carbon dioxide + water

The word equation for the incomplete combustion of butane is:

butane + oxygen
carbon monoxide + water