Chapter Eleven

Question 1

Fuel

Answer 1

A substance with stored energy that can be released easily for use as heat or power

Question 2

Biofuels

Answer 2

• Fuels derived from plant material such as grains
• Renewable resource

Question 3

Three types of biofuel

Answer 3

• Biogas
• Biodiesel
• Bioethanol

Question 4

Units of energy

Answer 4

• Si (international system on units)
• kJ
• MJ
• GJ
• TJ

Question 5

Fossil fuels

Answer 5

• Non renewable resource
• Formed from ancient plants, animals and microorganisms

Question 6

Sustainability

Answer 6

The combination of meeting the long-term ongoing needs of society while still meeting short-term demands

Question 7

Where is natural gas found

Answer 7

• Gas reservoirs between layers of rocks
• As a component of petroleum deposits
• In coal deposits
• Trapped in shale rock

Question 8

Fracking

Answer 8

Fracturing a rock or coal to release the natural gas

Question 9

How is bioethanol created

Answer 9

Through the process of fermentation

Question 10

How is biodiesel created

Answer 10

Esters are produced through a chemical reaction between vegetable oils or animal fats and an alcohol

Question 11

How is biogas formed

Answer 11

Released in the breakdown of organic waste through anaerobic bacteria

Question 12

Fermentation

Answer 12

The chemical breakdown of a substance by bacteria, yeasts, or other microorganisms, typically involving effervescence and the giving off of heat

Question 13

Combustion reaction

Answer 13

Burning fuel in the presence of oxygen

Question 14

Complete combustion happens when

Answer 14

Oxygen is plentiful

Question 15

What does a complete combustion produce

Answer 15

Co2 and H2O

Question 16

Incomplete combustion happens when

Answer 16

Oxygen is limited

Question 17

What does incomplete combustion produce

Answer 17

CO or C

Question 18

Greenhouse gas effect

Answer 18

Heat being trapped in the earths atmosphere by greenhouse gases

Question 19

Enhanced greenhouse effect

Answer 19

The change in weather patterns and climate due to increasing levels of greenhouse gas

Question 20

Carbon content

Answer 20

The amount of carbon present

Question 21

How to calculate carbon content

Answer 21

Change the % of carbon content to a fraction and multiply by the mass of the substance

Question 22

Energy content

Answer 22

The chemical energy available from a substance

Question 23

The energy released when n mols of fuel burns is given the equation

Answer 23

Energy = n X ΔHc

Question 24

Energy content per gram

Answer 24

Heat of combustion per gram/ molar mass

Question 25

Stoichiometry

Answer 25

The study of ratios of moles of substances

Question 26

Law of conservation of mass

Answer 26

In a chemical reaction the total mass of all products is equal to the mass of all reactants

Question 27

Mole ratio equation

Answer 27

n (unknown chemical) = coefficient of unknown chemical/coefficient of known chemical X n (known)

Question 28

Mass-mass stoichiometry

Answer 28

n = m/M
Moles = mass in grams divided by molar mass

Question 29

Factors affecting choosing a fuel

Answer 29

• Energy released per unit of mass or unit of volume
• Availability and cost
• Ease of transport
• Hazards
• Social, economic and political values

Question 30

Energy efficiency

Answer 30

The percentage of energy from a source that is converted to useful energy