organics I 4.5

Question 1

what is crude oil

Answer 1

mixture of hydrocarbons

Question 2

what happens to the colour of the fractions as the boiling point increases

Answer 2

darker

Question 3

what happens to the viscosity of the fractions as the boiling point increases

Answer 3

become more viscous

Question 4

how many fractions are there

Answer 4

6

Question 5

what are fractions lowest bp - highest

Answer 5

refinery gases
gasoline
kerosene
diesel
fuel oil
bitumen

Question 6

how does the molecular mass change as the boiling point increases

Answer 6

increases

Question 7

use of refinery gases

Answer 7

fuel for home cooking

Question 8

use of gasoline

Answer 8

fuel for cars

Question 9

use of kerosene

Answer 9

fuel for aircraft

Question 10

use of diesel

Answer 10

fuel for trains

Question 11

use of fuel oil

Answer 11

fuel for ships

Question 12

use of bitumen

Answer 12

making roads

Question 13

how are fractions separated

Answer 13

fractional distillation

Question 14

how does fractional distillation work

Answer 14

1. heated crude oil vapours enter the column
2. vapours rise until they reach their boiling point, when they condense
3. different vapours condense at different heights due to their different boiling points
4. similar vapours condense together as a fraction

Question 15

how does temperature vary in the distillation column

Answer 15

the bottom is hot and the top is cooler

Question 16

alkanes general formula

Answer 16

CnH2n+2

Question 17

what are alkanes made from

Answer 17

simple molecules containing C and H atoms held together by covalent bonds

Question 18

alkane 1 carbon name

Answer 18

methane

Question 19

alkane 2 carbon name

Answer 19

ethane

Question 20

alkane 3 carbon name

Answer 20

propane

Question 21

alkane 4 carbon name

Answer 21

butane

Question 22

alkane 5 carbon name

Answer 22

pentane

Question 23

what is display formula

Answer 23

a diagram showing the position of every atom and every bond

Question 24

what is structural formula

Answer 24

shows the structure of the molecule in one line

Question 25

what is molecular formula

Answer 25

show show many carbon and hydrogen atoms there are

Question 26

what is empirical formula

Answer 26

shows the simplest whole-number ratio

Question 27

what is a homologous series

Answer 27

similar chemical reactions trends in physical properties same general formula

Question 28

what is an isomer

Answer 28

a molecule with the same molecular formula but different structural formula

Question 29

what makes isomers different

Answer 29

branching in the carbon chain

Question 30

why are most alkanes used as fuels

Answer 30

they release a lot of energy when combusted

Question 31

when does complete combustion occur

Answer 31

when there is excess oxygen

Question 32

alkane + oxygen -->

Answer 32

carbon dioxide + water

Question 33

when does incomplete combustion occur

Answer 33

when there isn't enough oxygen

Question 34

what does incomplete combustion release

Answer 34

carbon monoxide and soot

Question 35

why do incomplete reactions make alkanes less useful

Answer 35

releases less energy

Question 36

what does the combustion of alkanes as fuels release

Answer 36

carbon dioxide, nitrogen oxides, sulphur dioxide

Question 37

how do alkanes react with halogens

Answer 37

swapping one hydrogen atom for one halogen atom

Question 38

what type of reaction is it when a halogen reacts with an alkane

Answer 38

substitution reaction

Question 39

what are the requirements for alkanes to react with halogens

Answer 39

UV light, as the alkane is not reactive

Question 40

how does crude oil compare to other alkanes

Answer 40

much longer than shorter ones

Question 41

what does cracking do

Answer 41

breaks down longer alkanes into smaller more useful ones

Question 42

what conditions are needed for cracking

Answer 42

temperature - 650 degrees catalyst - aluminium oxide

Question 43

long alkane -->

Answer 43

shorter alkane + alkene

Question 44

alkenes general formula

Answer 44

CnH2n

Question 45

what is the difference between alkanes and alkenes

Answer 45

alkenes have one C=C double-bond

Question 46

what does unsaturated mean

Answer 46

they have a double C=C bond

Question 47

what does saturated mean

Answer 47

they don't have a double C=C bond

Question 48

are alkenes saturated or unsaturated

Answer 48

unsaturated

Question 49

are alkanes saturated or unsaturated

Answer 49

saturated

Question 50

what type of reaction is alkene + bromine

Answer 50

addition reaction

Question 51

does an alkene +bromine reaction require uv light

Answer 51

no, alkenes are more reactive than alkanes

Question 52

what colour does the mixture turn in an alkene + bromine reaction

Answer 52

orange --> colourless, bromine is used up in the reaction

Question 53

when does an addition polymer form

Answer 53

when molecules with a C=C double bond add into chains

Question 54

what are the small molecules that add together called

Answer 54

monomers

Question 55

what are the long chains that form when added together called

Answer 55

polymers

Question 56

how are addition polymers represented

Answer 56

repeating units

Question 57

common uses for poly(ethene)

Answer 57

drinks bottles, shopping bags

Question 58

common uses for poly(propene)

Answer 58

storage boxes, climbing ropes

Question 59

common uses for poly(chloroethene)

Answer 59

wire insulation, drainpipes

Question 60

poly(tetrafluoroethene)

Answer 60

non-stick coating

Question 61

how to dispose of addition polymers

Answer 61

reuse, recycle, incinerate, landfill

Question 61

how to dispose of addition polymers

Answer 61

reuse, recycle, incinerate, landfill