organic chemistry
what is petroleum used for
-transport -burned for heat -used as feedstock of chemicals
what is petroleum
an organic compound -a hydrocarbon
key ideas behind refining petroleum
-chain length increases increase the boiling point -compounds will boil if heated enough -can collect different compounds at different points in the tower
fractional distillation
compounds are separated into different fractions
trends in fractions from fractional distilation boiling point range 20-100
-low viscosity -flammable -volatile
trends in fractions from fractional distillation boiling range 100-150
-more viscous -flammable -less volatile
trends in fractions from fractional distillation boiling range 150-200
more viscous -less volatile -less flammable
gasoline fraction uses and boiling point range
car engines 20-100
fuel oil fraction use and boiling point range
used in ships 100-150
bitumen fraction use and boiling point range
surface roads 150-200
four types of organic
-alkenes -alkanes -alcohol -carboxylic acids
how to identify which organic family a compound belongs to by their name
alkanes = -ane alkenes = -ene alcohol = -ol carboxylic acid = -oic acids
identifying amount of carbon atoms by compound name
meth = 1 eth = 2 prop =3 but = 4 pent = 5
homologus series
a family of similar compounds with the same functional group and chemical properties
functional group
atom or group of atoms in a molecule that dictate how compound reacts
chemical properties of alkanes
-saturated carbon bonds are all single covalent bonds -unreactive -burn well -form carbon dioxide, water vapour and heat when burnt -incomplete combustion leads to carbon monoxide - in substitution reactions one atom is replaced by one or more atoms
structural isomers
compounds with the same molecular formula but different structural formulas
cracking
breaking molecules into smaller ones when done using a catalyst it is catalytic cracking
benefits of cracking
it gives alkanes carbon-carbon double covalent bonds which makes them more reactive
alkane compounds
methane -butane -propane -ethane
alkenes
-hydrocarbons -form a homologous group - all contain a c=c double bond - unsaturated
key points about alkenes
-do not naturally occur -more reactive than alkanes
test for unsaturation
c=c bonds presence turns bromine colourless
what are alcohols
hydroxyl group -contain OH functional groups
why is ethanol important
-solvent -volatile -burns readily in oxygen -kills viruses and bacteria
methods to make ethanol
1 reacting ethene with steam 2 by fermentation
advantages to making ethanol by mixing ethene and steam
-fast reaction -can be done non-stop -gives pure ethanol
disadvantages of making ethanol with ethene and steam
-made from non-renewable source - requires lots of electricity -reversible reaction
advantages of making ethanol through fermentation
-uses renewable source -can use waste materials -takes place close to room temperature
disadvantages of making ethanol through fermentation
-needs lots of land -slow process -requires distillation to obtain ethanol -yeast stops reacting with ethanol after a certain level
why has ethanol become more popular as a fuel
- made from plant material -ethanol can be made in countries without petroleum -creates carbon dioxide wrn burned but crops are grown so there is minimal environmental impacts
carboxylic acids
functional group cooh -carboxyl group
two ways to make ethanoic acid
1 using a chemical agent 2 by fermentation
typical ethanoic acid reaction
-turns water litmus red -reacts with metals, bases and carbonates make salts
how to make an ester
two molecules join larger molecule with loss of the small molecule call a condensation reaction