compares fossils fuels and bio fuels(1.2) Flashcards
energy content
- energy content is the chemical energy of a substance
what happens to chemical energy when fuels are used
chemical energy is converted to a different of energy when fuels are used
energy transformation
- the total amount of energy is unchanged beavuse enegry can not be created or destroyed . however the all energy is not converted to one specific form.
energy efficiency
- used to describe the percentage of enegry from a source that is convered to useful energy
electricity production
- chemical energy is harnessed through combustion of fuels
- reactants combine with oxygen to produce carbon dioxide and water. thermal energy is released from the combustion of fuels which can then be converted into electrical energy
fuel for transport
- crude oil is the most used source for transoprt.
- as through fractional distillation, LPG, petrol, Petro diesel and kerosene are produced
petrol
- mixture of hydrocarbons including octane. (combustion to get energy)
LPG
- liquid petroleum gas
- can be used in cards for fuel
- propane for combustion
-cheap, may blow if car crash
ethanol
- ethanol can be blended with petrol to create e10 (10% ethanol)
- the presence of ethanol reduces the emissions of particulates and gases such as oxides of nitrogen, but higher levels of ethanol can damage engines
- a larger mass of ethanol is required to provide the same amount of energy, ethanol has a lowe energy content due to the presence oc oxygen in ethanol
pros and cons of biofuels
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
pros and cons of fossil fuels
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