fuels

Question 1

fuel

Answer 1

a fuel is a substance that can be reacted with other substances leading to the release of energy that can be harnessed for a specific purpose

Question 2

renewable

Answer 2

a resource that can be replenished by natural processes within a relatively short period of time.

Question 3

non-renewable

Answer 3

a resource that cannot be replenished by natural processes within a relatively short period of time.

Question 4

fossil fuels

Answer 4

• fuels derived from living matter compressed underground for millions of years
  -non-renewable
• crude oil/ petroleum

Question 5

bio fuels

Answer 5

-derived from plant matter and can be produced at the same rate we consume it
-renewable
- biogas, bioethanol, biodiesel

Question 6

biogas

Answer 6

• produced by the anaerobic bacterial decomposition of organic wastes
  -mainly contained by methane(fuel) and bits of carbon dioxide( no fuel)
  -trace amount of other products(H20,o2)
• it releases less energy as it contains less methane than fossil fuels

Question 7

bioethanol

Answer 7

-produced by the fermentation of glucose by yeast
-often used for vehicles
-blend of 90% petrol and 10% of ethanol

Question 8

biodiesel

Answer 8

-produced by using plant oils or animal fats(triglycerides) in a transesterification reaction
- also known as fatty acid methy ester/FAME

Question 9

pros and cons of fossil fuels

Answer 9

PROS:
- high energy content
-easy to release energy from
-relatively easy to obtain
- extensive existing infrastructure
CONS:
- non renewable
- emits large amounts of CO2, a potent green house gas
- release other toxic chemicals ,e.g. nitrogen and sulfur oxide
- extraction extremely damaging to the environment

Question 10

pros and cons of biofuels

Answer 10

PROS:
-renewable
- relatively carbon neutral
-burn more cleanly than fossil fuels, less harmful chemicals released
- easy to source material used for production, can be produced from crop waste
CONS:
- lower energy content than fossil fuels
- can be complicated and costly to produce
-can require large amounts of water to grow crops

Question 11

biodiesel vs petrodiesel

Answer 11

biodiesel:
- produced via transesterification of waste oils
- burns more cleanly than Petro diesel, producing less particulates and other toxic chemicals
- stronger dipole - dipole bonding make it viscous, can clog at low temps
PETRODIESEL
- extraced from crude oil
- produces particulates and other toxic chemicals when combusted
- large hydrocarbon chains experience only weaker dispersion forces, less viscous