Organics 1 Flashcards

1
Q

What is crude oil?

A

A mixture of hydrocarbons

(which have different boiling points!)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is a hydrocarbon?

A

A molecule containing carbon and hydrogen only

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why is crude oil considered to be a non-renewable energy source?

A

Crude oil takes many million of years to form in the Earth’s crust through heat and high pressures.

It does not renew itself at a sufficient rate for sustainable use

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Name the first four hydrocarbon in the alkane homologous series.

(Monkeys eat peeled bananas!)

A

methane

ethane

propane

butane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is an alkane?

A

A hydrocarbon with single C-C bonds only- no C=C double bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the general formulae for alkanes?

A

CnH2n+2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the general formulae for alkenes

A

CnH2n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the name for C8H18 and what homologous series is it from?

A

octane

it is an alkane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Alkanes only have a single bond between the carbon atoms.

What effect does this have on their reactivity?

What name is used for this sort of hydrocarbon?

A

Large number of hydrogen atoms blocking the C-C bond makes it difficult to get to and makes them less reactive.

They are said to be saturated with hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the name for C7H14 and what homologous series is it from?

A

heptene

It is an alkene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name the two alkanes with 9 and 10 carbons and give their molecular formulae

A

Nonane - C9H20

Decane - C10H22

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How do molecules in a particular homologous series relate?

A

- they have trends in physical properties

- they have similar chemical properties

  • they have the same functional group
  • they differ by CH2 groups
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the display formula for methane?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Alkenes have a double bond between the carbon atoms.

What effect does this have on their reactivity?

What name is used for this sort of hydrocarbon?

A

There are fewer hydrogen atoms blocking the C=C bond. This makes it easy to get to and makes them more reactive.

They are said to be unsaturated

(They are not saturated with hydrogen!)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Alkanes only have a single bond between the carbon atoms.

What effect does this have on their reactivity?

What name is used for this sort of hydrocarbon?

A

Large number of hydrogen atoms blocking the C-C bond makes it difficult to get to and makes them less reactive.

They are said to be saturated with hydrogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Name the two alkanes with 5 and 6 carbons and give their molecular formulae

A

Pentane C5H12

Hexane C6H14

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name the two alkanes with 9 and 10 carbons and give their molecular formulae

A

Nonane - C9H20

Decane - C10H22

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name the two alkanes with 7 and 8 carbons and give their molecular formulae

A

Heptane - C<span>7</span>H<span>16</span>

Octane - C<span>8</span>H<span>18</span>

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Name the two alkanes with 9 and 10 carbons and give their molecular formulae

A

Nonane - C9H20

Decane - C10H22

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the display formula for pentane?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What happens to the intermolecular forces as you go down the alkane group?

How do you know?

A

There are more intermolecular forces down the alkane group

The boiling point increases down the group- more energy needed to overcome the intermolecular forces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the structural formulae for ethane?

A

CH3CH3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the trend in volatility in the alkane group?

A

Hydrocarbons are more volatile the shorter their chain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the structural formulae for propane?

A

CH3CH2CH3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What property allows hydrocarbon fractions to be separated?

Name the method used to separate them.

A

The hydrocarbon fractions have different boiling points

They are separated using fractional distillation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What happens to the viscosity as the carbon chain increases in length?

A

Viscosity increases as chain length increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Name the main fractions from crude oil

Hint: there are seven!

A

Refinery gases

Gasoline

Naptha

Kerosene

Diesel

Fuel Oil

Bitumen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What happens to the bointing point as the carbon chain increases in length?

A

Boiling point increases as the carbon chain increases

methane is a gas, petrol is a liquid at room temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is an isomer?

A

Compounds with the same molecular formula but different structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What happens to the colour as the carbon chain increases in length?

A

The hydrocarbon gets darker in colour as you increase the carbon chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the addition reaction for propene and bromine water?

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Why do you think alkenes are more ‘useful’ in the chemical industry?

A

They have C=C and so are more reactive

They can be used to make polymers and other chemical products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What would you observe if methane is reacted with bromine in the presence of UV light?

A

Orange to colourless after about 20 minutes

34
Q

What type of reaction is this?

A

Substitution

The hydrogen was substituted with the bromine atom

35
Q

What type of reaction is this?

A

addition reaction

double bond is broken and two bromine atoms are added to either side of this

36
Q

What is the test for alkenes?

A

add bromine water

turns orange to colourless

alkanes need UV light for 20 minutes to turn colourless

37
Q

What is combustion?

A

The chemical reaction of a fuel and oxygen

Complete combustion will produce carbon dioxide and water

the reaction is exothermic

38
Q

What are the main products for the incomplete combustion of methane?

A

carbon monoxide, carbon dioxide and water

39
Q

What is the reaction for complete combustion of methane?

A
40
Q

Why is carbon monoxide dangerous?

A

It is toxic

  • it binds irreversibly to your haemoglobin
  • it reduces the capacity of your blood to carry oxygen
  • person dies of asphyxiation
41
Q

Most fuels contain sulfur.

What is the environmental impact of this?

A

sulfur reacts with oxygen to form sulfur dioxide

non-metal oxides form acid when in water

sulfuric acid forms- acid rain

-lakes become acidic- killing aquatic life

-acid rain leaches minerals from soil- killing trees

42
Q

How can you tell that a fraction from a distillation tower still contains a mixture of hydrocarbons?

A

The fraction boils over a range of temperature rather than exactly at one temperature- it is not pure

43
Q

Fuel are burnt in air which contains 78% nitrogen

What is the environmental impact of this?

A

nitrogen reacts with oxygen to form nitrous oxide

non-metal oxides form acid when in water

nitric acid is formed- acid rain

-lakes become acidic- killing aquatic life

-acid rain leaches minerals from soil- killing trees

44
Q

What product of combustion is most dangerous for the environment and why?

A

Carbon dioxide

CO2 is a greenhouse gas which may lead to global warming

45
Q

What are the products which can form from the thermal decomposition (cracking) of heptane?

A

C2H4 & C5H12

Must have 7 carbons

one must be an alkene and one alkane

46
Q

Long (less useful) hydrocarbons are heated and passed over a hot aluminium oxide catalyst.

This breaks up the long chain molecules into a smaller alkane and alkene.

These smaller chain hydorcarbons are more useful

What is this called?

A

Cracking

47
Q

What are the conditions for cracking?

A

Hot aluminium oxide catalyst

600 - 700 °C

48
Q

Explain why cracking is important to the chemical industry?

A

Forms smaller more useful alkanes which are in higher demand

Forms alkenes which can be used to make polymers

Cracking balances supply and demand of these smaller chained alkanes and alkenes

49
Q

The products of cracking long chain hydrocarbons are shorter chained alkanes and alkenes.

How could you test to show that an alkene is produced?

A

Collect gas by downward displacement

Place a few drops of bromine water

shake

should turn orange to colourless

50
Q

What is the name of the polymer formed form ethene?

A

poly (ethene)

51
Q

What is the process that links together small double bonded molecules (monomers) to form a long chain molecules.

A

addition polymerisation

52
Q

What is the name of the polymer formed form propene?

A

poly (propene)

53
Q

What is the name of the polymer formed form chloroethene?

A

poly (chloroethene)

54
Q

What is the name of the polymer formed form tetrafluoroethene?

A

poly (tetrafluoroethene)

55
Q

Which type of polymerisation is shown below

A

addition polymerisation

56
Q

Which type of polymerisation is shown below?

A

Condensation polymerisation

57
Q

What are the differences between addition polymerisation and condensation polymerisation?

A
  1. Addition polymers- one type of monomer

Condensation polymers - two different monomer

OR

  1. Addition polymerisation forms a pure polymer

Condensation polymerisation forms the polymer and a small molecule (e.g. H2O)

58
Q

Describe the environmental impact of plastics and what can be done

A

Plastic are inert (cannot be broken down by microorganisms) AND they give off toxic gases when burned

(make them biodegradable, recycle them, reduce use, reuse them)

59
Q

Name the monomer for this polymer

A

ethene

60
Q

Name the monomer for this polymer

A

chloroethene

61
Q

Name the monomer for this polymer

A

tetrafluoroethene

62
Q

Name the monomer for this polymer

A

propene

63
Q

Is this hydrocarbon saturated or unsaturated?

A

Unsaturated

Contains a C=C double bond

64
Q

What homologous series does this hydrocarbon belong to?

What is its general formula?

A

alkenes

CnH2n

65
Q

What homologous series does this hydrocarbon belong to?

What is its empirical formula?

A

alkanes

C5H12

empirical formula is simplest ratio

5:12 is already the simplest ratio

66
Q

Cracking is a thermal decomposition reaction.

True or false?

A

true

67
Q

Bromine water added to an alkene is an example of an addition reaction?

True or false?

A

True

double bond opens and two bromine atoms are added to either side of the double bond

68
Q

Monomers used to make addition polymers are said to be saturated?

True or false?

A

False

Monomers are alkenes and contain double bonds

They are unsaturated hydrocarbons

69
Q

What is the main use of polyethene?

A

plastic bags and bottles

70
Q

What is a main use of polypropene

A

crates and buckets

71
Q

What are the main uses of polychloroethene?

A

window frames, plastic pipes

72
Q

What is the main use of tetrafluoroethene

A

non-stick coating on pans

73
Q

Name this organic compound

A

but-1- ene

  • longest C chain is 4 Cs*
  • double bond after 1st C*
74
Q

Name this organic molecule

A

2 bromo 3 methyl but-2-ene

  • Br on 2nd C*
  • CH3 - methyl on 3rd C*
  • double bond after 2nd C*
75
Q

Name this organic compound

A

2,4 dimethyl 3 ethyl hexane

  • longest chain 6 Cs long*
  • methyl group on 2nd and 4th C*
  • ethyl group on 3rd C*
76
Q

What is a fuel?

A

A material which is burned to release energy

(via heating and radiation (light))

77
Q

In incomplete combustion, a poisonous gas and solid may be formed. Name these.

A

carbon monoxide and soot

78
Q

When methane reacts with bromine it forms bromomethane. UV light is needed to remove a hydrogen and replace it with a bromine atom.

What type of reaction is this?

A

substitution

79
Q

When methane reacts with bromine it needs a particular condition. Describe this condition and the resulting product.

A

UV light for 20 minutes

bromomethane

80
Q

What do you call the hydrocarbon with a total of 8 carbon atoms in its chain with a double bond after its 3rd carbon?

A

oct-3-ene

81
Q

What do you call the hydrocarbon with five carbon atoms in its chain and a double bond after its 1st carbon?

A

pent-1-ene