organic chem fuels Flashcards
what is a fuel
A fuel is a substance which when burned, releases heat energy
what are common fossil fuels
coal, natural gas and hydrocarbons (eg methane and propane which can be obtained from petroleum)
what is petroleum and how can it be made useful
a mixture of hundreds of hydrocarbons, as a mixture it is not very useful but upon refining (fractional distillation) its separate fractions can be very useful
in refining, what happens as chain length increases
the boiling points of compounds rise
once petroleum or crude oil is heated enough, how can it be collected again
if petroleum is heated enough, the compounds will boil to form gasses, if these rise up a tall tower they will cool as they rise and condense at different heights depending on their boiling point
what is the first fraction called? no of carbon atoms? and use for the fraction
refinery gas
c1 to c4
used for cooking and heating
what is the second fraction called? no of carbon atoms? and use for the fraction
gasoline/petrol
c5 to c6
used to fuel cars
what is the third fraction called? no of carbon atoms? and use for the fraction
naptha
c6 to c10
monomer/starting point/feedstock for many chemicals and plastics
what is the fourth fraction called? no of carbon atoms? and use for the fraction
paraffin/kerosine
c10 to c15
fuel for aircraft, oil stoves and lamps
What is the fifth fraction called? chain length? uses?
Diesel oil
C15 to C20
fuel diesel engines
what is the sixth fraction called? no of carbon atoms? and use for the fraction
fuel oil
c20 to c30
fuel for power stations, ships and home heating systems
what is the seventh fraction called? no of carbon atoms? and use for the fraction
lubricating fraction
c30 to c50
oil for car engines and machinery, waxes and polishes
what is the eighth fraction called? no of carbon atoms? and use for the fraction
bitumen
c50+
used to make roads
IS SOLID
what happens as chain length increases
viscosity increases, boiling point increases
flammability and volatility decrease
where does refinery gas condense and as chain length increases where do the gasses condense
refinery: at the top of the fractionating tower
as chain length increases, the gasses condense lower in the fractionating tower
what do the properties of each fraction dictate
the properties dictate the uses
why is petrol/gasoline best suited for fuel in cars
this fraction is thin, runny, volatile and highly flammable which is suitable for burning in car engines; where the fuel must catch fire with just a spark
why is fuel oil best suited for fuel in ships
this fraction is thicker and much less volatile, this suits ships and furnaces where a volatile fraction might cause an explosion
what is bitumen mixed with and why is it ideal for road building
bitumen is a soft solid that does not burn until over 200 degrees celsius
it is mixed with stone chips when melted
upon further refinery what is found in refinery gas (fraction 1)
methane, ethane, propane and butane
what must be removed from the liquid fuel fractions and why
sulfur as sulfur burns to give sulfur dioxide which causes acid rain
What type of reaction is burning fuels
endo or exo
combustion reaction
exo
What are the 2 types of combustion reaction
conditions for both
Products
Complete combustion - sufficient oxygen supply - co2 and h20
incomplete - insufficient oxygen supply - CO (carbon monoxide
What are the 2 types of combustion reaction
conditions for both
Products
Complete combustion - sufficient oxygen supply - co2 and h20
incomplete - insufficient oxygen supply - CO (carbon monoxide