Topic 7 - Organic Chemistry

Question 1

what is in a hydrocarbon ?

Answer 1

HYDROGEN AND CARBON

Question 2

what do alkanes have ?

Answer 2

SINGLE carbon bonds

Question 3

what is the general formula for an alkane ?

Answer 3

CnH2n+2

Question 4

what is a homologous series ?

Answer 4

a family with the same general formula and react in a similar way

Question 5

what is an alkane ?

Answer 5

saturated compounds

- each carbon atom forms 4 single covalent bonds

Question 6

what are the properties of a shorter carbon chain ?

Answer 6

• less viscous
• lower boiling point
• pale in colour
• very flammable

Question 7

what happens in the complete combustion of a hydrocarbon ?

Answer 7

• there is A LOT of energy
• only waste product are carbon dioxide and water vapour
  hydrocarbon + oxygen —–> carbon dioxide+ water + energy

Question 8

what is crude oil ?

Answer 8

a fossil fuel that is a mixture of lots of different hydrocarbons
made from the remains of plants and animals that have been compressed with a high temperature

Question 9

what is fractional distillation ?

Answer 9

a method to separate the different compounds in crude oil

Question 10

how does fractional distillation work ?

Answer 10

• the oil is heated
• gas enters the fractionating column at the bottom where it is the hottest
• longer hydrocarbons with high boiling points condense early on
• the shorter hydrocarbons with lower boiling points condense much later
• at the end your oil mixture is separated into into different fractions containing a mixture of hydrocarbons with a similar boiling point

Question 11

what are some uses of crude oil ?

Answer 11

• fuel for transport

- petrochemical industry

Question 12

what is cracking ?

Answer 12

the splitting of long - chain hydrocarbons as short chained hydrocarbons are much more useful
- fuels

Question 13

what are the two types of cracking ?

Answer 13

• catalytic cracking

- steam cracking

Question 14

what do alkenes have ?

Answer 14

a carbon DOUBLE bond

Question 15

what are alkenes ?

Answer 15

UNsaturated compounds

Question 16

what is the general formula for alkenes ?

Answer 16

Cn H2n

Question 17

what happens when you burn an alkene ?

Answer 17

• incomplete combustion
• smoky flame (yellow)
  alkene = oxygen —-> carbon+ carbon monoxide + carbon dioxide + water

Question 18

what is an alkenes function group ?

Answer 18

c=c

Question 19

what happends when bromine water is added to an allkene and alkane ?

Answer 19

alkane = NO CHANGE 
alkene = orange goes colourless

Question 20

what happens when a steam reacts with an alkene ?

Answer 20

an alcohol is formed

Question 21

what is a polymers ?

Answer 21

lots of monomers join together

Question 22

what is a monomer ?

Answer 22

small molecules

Question 23

what monomer makes up addition polymers ?

Answer 23

unsaturated monomers with double bonds

Question 24

what is addition polymerisation ?

Answer 24

when lots of unsaturated monomers open up their double bonds to join together to form a polymer chain

Question 25

what is the function group of an alcohol?

Answer 25

-OH

Question 26

what is the general formula of an alcohol ?

Answer 26

CnH2n+1OH

Question 27

what are the properties of the first 4 alcohols ?

Answer 27

- flammable - complete combustion produces carbon dioxide and water - soluble in water - react with sodium to produce hydrogen - oxidise alcohols produce CARBOXYLIC acids

Question 28

what are alcohols used for ?

Answer 28

- solvents | - fuel

Question 29

how can ethanol be made ?

Answer 29

``` FERMENTATION 37 degrees anaerobic respiration slightly acidic - avoid denaturing enzymes ```

Question 30

what is the functional group of a carboxylic acid ?

Answer 30

-COOH

Question 31

what do they produce when reacted with carbonates ?

Answer 31

salt (-anoate) water carbon dioxide

Question 32

what happens when a carboxylic acid dissolves in water ?

Answer 32

- ionises and releases H+ ions making the solution acidic | - it is a weak acid as it doesn't FULLY ionise

Question 33

what is the function group of an ester ?

Answer 33

- COO

Question 34

how is an ester formed ?

Answer 34

alcohol and a carboxylic acid react to form an ester and water

Question 35

what is a condensation polymer ?

Answer 35

monomers with different function groups | for each new bond a small molecule is lost

Question 36

what makes up an amino acid ?

Answer 36

a basic amino acid group (NH2) and an acidic carboxyl group

Question 37

what is a protein ?

Answer 37

a polymer of amino acids | chains of polypeptides

Question 38

what does an amino acid dorm through condensation polymerisation ?

Answer 38

POLYPEPTIDES

Question 39

what is DNA from ?

Answer 39

- nucleotides - double helix - found in nucleus