Unit 7: Organic chemistry

Unit 7: Organic chemistry

what is the general formula for alkanes

CnH2n+2

alkanes are … molecules because the carbon atoms are fully … to the … atoms

saturated

bonded

hydrogen

what is a hydrocarbon

a molecule made up of only carbon and hydrogen

features of crude oil

• made over millions of years from remains of plankton in mud

• found in rocks

• mixture of hydrocarbons

as the size of hydrocarbon increases, the … the viscosity (runny/ …)

higher

thickness

as the size of hydrocarbon increases, the … the flammability

lower

as the size of hydrocarbon increases, the … the boiling point

higher

what do hydrocarbon fuels release when combusted (burned)

energy

are carbon and hydrogen atoms oxidised or reduced in combustion

oxidised

what happens if the oxygen supply is unlimited in the combustion of hydrocarbons and what is this reaction called

the reaction also produces CO2 and water which is called complete combustion

what are the steps to the fractional distillation of crude oil

1. crude oil is heated at very high temp causing it to boil

2. crude oil vapour is fed into the column

3. hydrocarbon vapours rise up the column

4. hydrocarbons condense when they reach their boiling point

5. liquid fractions are then removed

6. remaining hydrocarbon move up column

7. they condense when they reach their boiling points

what are some fractions used for in the fractional distillation of crude oil

feedstock which is a chemical used to make other chemicals

what is cracking

when a long-chain alkane is broken down to produce smaller molecules

what does cracking make

alkenes which have at least one carbon to carbon double bond

what are the conditions needed for cracking

• high temperature

• high pressure

what are alkenes useful for

• to make polymers

• used as a starting material for chemicals

how can we test for alkenes

1. shake alkene with bromine water

2. bromine turns colourless if alkene is present

what is the general formula for alkenes

CnH2n

alkenes are … because they have … fewer hydrogen atoms than the alkane with the same number of … atoms

unsaturated

two

carbon

what does ethene look like

what does propene look like

what does butene look like

what does pentene look like

what is a functional group

part of a molecule that determines the way it reacts

what is a homologous group

members with the same functional group

what does combusting and alkene produce and what is this reaction called

CO2, water, unburnt carbon particles

incomplete combustion

what does reacting an alkene with hydrogen produce and what is this reaction called

an alkane

hydrogenation

what does reacting an alkene with water (in the form of steam) produce and what is this reaction called

an alcohol

hydration

what type of reaction is hydration

reversible reaction

what are the conditions of hydration

• 300 degrees Celsius

• 7 atm (pressure)

• phosphoric acid catalyst

what does reacting an alkene with a halogen produce and give an example

di(start of halogen name)(alkane name)

e.g. dichloroethane

what does methanol look like

what does ethanol look like

what does propanol look like

what does butanol look like

what is the functional group of alcohols

OH

what are the uses of alcohols

• fuels

• solvents

• drinks

what are the advantage of the hydration of ethene

• high yield of ethanol produced

what are the disadvantages of the hydration of ethene

• requires lots of energy

• ethene in the reaction comes from crude oil which is non-renewable

what is the equation for the fermentation of sugar and at what temperature should it be carried out at

30 degrees Celsius

what are the advantages of the fermentation of sugar

• not a lot of energy required

• reaction comes from plants so is renewable

what are the disadvantages of the fermentation of sugar

• product is an aqueous solution

alcohols are … in water and form … solutions

soluble

neutral

as number of carbon atoms increase, solubility …

decreases

what is produced in the reaction between alcohols and sodium

bubbles of hydrogen and sodium ethoxide

what is produced in the reaction between alcohols and oxidising agents

carboxylic acid and water

what does the combustion of alcohol produce

CO2 and water

are carboxylic acids weak or strong acids in water

weak

what does methanoic look like

what does ethanoic look like

what does propanoic look like

what does butanoic look like

what is the functional group of carboxylic acids

C=O

I

OH

what does the reaction between carboxylic acids and metal carbonates produce

a salt, water and CO2

what does the reaction between carboxylic acids and alcohols produce

an ester and water

what type of reaction is the reaction between carboxylic acids and alcohols

reversible reaction

what is required in the reaction between carboxylic acids and alcohols

sulfuric acid as a catalyst

what is a polymer

thousands of small, identical molecules

what is a monomer

the small, identical molecule in a polymer

are the monomers alkanes or alkenes in addition polymers

alkenes

addition polymers have the same … as the monomer

atoms

does a monomer have a double or single carbon to carbon bond

double

does a polymer have a double or single carbon to carbon bond

single

how do you name a polymer and give an example

poly(name of monomer/ alkene)

e.g. polyethene

what does a repeating unit look like in addition polymers and does it contain a double bond

no

in condensation polymers, the monomers are not … . when the monomers react, we … small molecules such as …

alkenes

lose

water

with condensation polymers, we start with two different … . each monomer has to of the same …

monomers

functional groups

what is a polyester

a polymer with thousands of monomers

what does a repeating unit look like in condensation polymers

what can amino acids react to form

a condensation polymer and water

what is a polypeptide

a polymer made from one type of amino acid

what is a protein

a polymer made from different amino acids

what does glycine look like

what are the functional groups of glycine

what does DNA consist of

two polymer chains made from monomers called nucleotides

what are the naturally occurring polymers and what are they polymers of

1. proteins → polymers of amino acids

2. starch → polymer of glucose

3. cellulose → polymer of glucose