C1 Flashcards
What is an alkene and what is its formula?
Contain a double bond between two carbon atoms. This makes them much more reactive than alkanes. They are unsaturated.
AN UNSATURATED HYDROCARBON
CnH2n
What is an alkane and what is its formula?
Contain single c to c bonds. They are saturated.
A SATURATED HYDROCARBON CONTAINING SINLGE C-C BONDS
CnH2n+2
What does saturated mean?
Only contains single c-c bonds
What does unsaturated mean?
Contains at least one c=c double bond
What is crude oil?
A mixture of a very large number of compounds which are useful to us most of which are hydrocarbons with different boiling points
How do we separate crude oil?
Fractional distillation
Why is it possible to separate the fractions of crude oil by fractional distillation?
The compounds have different boiling point
What are the properties of the top of the column in fractional distillation?
Small molecules: •low boiling point •very volatile •flows easily •ignites easily
What are the properties of the bottom of the column in fractional distillation?
Large molecules: •high boiling point •not very volatile •doesn't flow easily •doesn't ignite easily
What is the definition a hydrocarbon?
Molecules containing only hydrogen and carbon atoms
What is the equation for incomplete combustion?
CH4+O2=CO+C+2H2O
What is the equation for complete combustion?
CH4+2O2=CO2+2H2O
Why does incomplete combustion occur?
there isn’t enough oxygen to react with
What does incomplete combustion produce?
Carbon monoxide, carbon and water
What effect does carbon monoxide have on humans?
it is poisonous and harmful. Is also a greenhouse gas
What is Sulphur Dioxide?
Compound which contains one sulphur atom and two carbon atoms in each molecule and is present in acid rain.
How are oxides of nitrogen produced when fuels burn in car engines?
Nitrogen and oxygen react together in the high temperature of the car engine to form nitrogen oxide
What are biofuels?
Anything which comes from a living organism
OR
A fuel obtained from a grown crop such as ethanol from sugar cane
List 4 disadvantages of biofuels
1) using fuel instead of food means less food is produced (leads to higher prices)
2) Both fossil fuels and biofuels produce CO2
3) Energy used for machinery may be more than what is produced.
4) Decrease in biodiversity
What is Cracking?
Process of breaking large molecules into smaller more useful ones by heating or using a catalyst
List the stages in cracking
*heat to vaporise the long alkanes
*vapours are then passed over a hot catalyst
(or mixed with steam at a very high temperature)
*thermal decomposition then occurs
What is a catalyst?
Substance that speeds up a reaction without being used up in the reaction
What are the products of cracking?
Cracking always produces two types of molecule: an alkane and an alkene
What is a polymer?
Material whose molecules are made up of many monomers
What is polymerisation?
Is when many monomers join together to form a long chain called a polymer
What two polymers would be made from the monomers ethene and propane?
poly(ethene) and poly(propane)
What name do we give the mouldable polymers that are made from alkenes?
Plastics