Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Science - continued > Hydrocarbons > Flashcards

Hydrocarbons Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What are hydrocarbons

A

Molecular compounds that only contain hydrogen and carbon

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

What is the general formula that all alkanes have

A

[the stuff in brackets is the small numbers] C(n)H(2n+2)

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

What is a homologous series

A

A series of molecules that have a general formula and vary in a single feature (such as carbon chain length)

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

When are the molecules saturated?

A

When all the carbon-carbon bonds are singular

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

Are alkanes saturated or unsaturated

A

Saturated

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

What is the name for 1, 2, 3 and 4 carbons in the chain

A

1 - meth
2 - eth
3 - prop
4 - but

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

When are hydrocarbons unsaturated

A

When there is one or more double covalent bond between adjacent carbon atoms

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

What is the general formula for alkenes

A

C(n)H(2n)

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

What is a functional group and an example of one

A

The carbon-carbon double bond is an example and it is a group of atoms that is mainly responsible for the molecule’s chemical properties

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

What is an isomer?

A

Molecules with the same molecular formula but different arrangements of atoms

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

How many isomers does butane have and what do the numbers in the name show

A

2
the 1 shows that the C=C bond starts at the end of the molecule
the 2 shows that the C=C bond is in the middle

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

When does complete combustion occur

A

When all the atoms from the hydrocarbon are used up

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What colour is bromine water

A

Orange-brown

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

What is the test that distinguishes between alkanes and alkenes and why is this

A

Alkanes do not form colourless solutions when mixed with bromine water but alkenes do because of the double carbon bond

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

What do the numbers in the product 1,2dibromoethane mean

A

They show that there are two bromine atoms and they’re attached to different carbon atoms- if it was 1,1 then they would only be attached to one carbon atom

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

What is an addition reaction?

A

Where the reactants combine to form one large product molecule and no other product

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

What is the formula for ethanol

A

C2H5OH

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

What is the ethanol in alcoholic drinks made of?

A

Sugars broken down from starch and seeds are germinated before using them to make ethanol as the enzymes in the seeds naturally break down the starch

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

What is the plant source of beer and whisky

A

barley seeds

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

What is the plant source of wine

A

grapes

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

What is the plant source of vodka

A

wheat seeds

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

What is fermentation

A

When the enzymes in the yeast (which is mixed with the water and plant sugars) turns the sugars into ethanol and carbon dioxide

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

Why is an air lock necessary when fermenting ethanol

A

The air lock in the neck of the jar allows CO2 out whilst still keeping air out as fermentation is a form of anaerobic respiration and only works without the presence of oxygen

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

What percentage of alcohol concentration does fermentation produce

A

No more than 15% otherwise it will kill the yeast cells

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

How are more concentrated alcohols made

A

Through fractional distillation as ethanol’s boiling point is lower than the boiling point of water

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

What do organic compounds consist of?

A

A central framework of carbon atoms onto which hydrogen and other atoms are attached

27
Q

What do all alcohols, alkenes and alkanes’ names end in?

A

alcohols -anol
alkenes -ene
alkanes -ane

28
Q

Give examples of common alcohol chemical properties

A
  • production of carbon dioxide and water in complete combustion
  • can be oxidised to form compounds called carboxylic acids
  • they react with reactive metals such as sodium, forming hydrogen gas as one of the products
29
Q

Give some examples of uses of alcohols

A
  • many used in solvents for cosmetics and medical drugs
  • methanol and ethanol are used as fuels and can be made from renewable sources
  • scientists are now working on developing butanol and propanol fuels from renewable resources
30
Q

Which fuel has the most and least amount of energy stored?

A

Petrol and methanol

31
Q

How do you compare the energy given out by different alcohols in combustion?

A
  • measure the mass of the alcohol bottle and cap and record the mass
  • place the bottle in the middle of a mat and use a measuring cylinder to add 100cm3 water into a conical flask
  • measure the initial temperature of the water
  • light the wick of the bottle and allow the water to get to around 40 degrees
  • measure the mass of the burner after placing the cap
  • calculate the mass of the alcohol burned to produce a 1 degree increase in temperature
32
Q

What happens to wine/beer/cider if it is left open?

A

It turns into vinegar due to a reaction between ethanol and oxygen - the product is a ethanoic acid

33
Q

What homologous group does ethanoic acid belong to?

A

Carboxylic acids

34
Q

What is the general formula for carboxylic acids

A

C(n)H(2n+1)COOH

35
Q

How are carboxylic acids formed

A

Usually through gentle oxidation of alcohols using oxidising agents such as hot copper oxide

36
Q

Give the properties of carboxylic acids

A
  • form solutions with a pH less than 7 (if soluble)
  • react with metals to form a salt and hydrogen
  • react with bases to form a salt and water
  • react with carbonates to form a salt, water and carbon dioxide
37
Q

Why do carboxylic acids have acidic properties

A

Due to the -COOH presence which in solution forms a hydrogen ion while the rest of the molecule forms the negative ion that makes salt

38
Q

What can vinegar be used for?

A

To test for carbonate rocks like chalk and limestone - the ethanoic acid ‘fizzes’ producing carbon dioxide gas

39
Q

What are plastics made of?

A

Polymers

40
Q

What is a polymer?

A

A large molecule made from lots of small molecules called monomers joined together - the process in which the monomers join together is called polymerisation

41
Q

What kind of average relative molecular mass does a polymer have?

A

A high relative molecular mass (anything from tens to thousands of millions) - as the polymer molecules can be any lengths, they cannot be given a specific relative mass

42
Q

What is addition polymerisation

A

Monomers react to form a polymer without the formation of by-products

43
Q

How do ethene molecules form poly(ethene)

A
  • Ethene molecules have a double covalent bond between the carbon atoms
  • One of the bonds in the double bond breaks open and another ethene molecule is added on
  • This happens again and again forming a long chain
44
Q

What does a repeating unit in a polymerisation equation show

A

It shows how the monomer has changed and how it repeats throughout the polymer chain

45
Q

What is a synthetic polymer and give an example

A

It is a polymer that is manufactured in a lab or factory and polythene is an example

46
Q

Give examples of some naturally occurring polymers

A

DNA, starch and proteins

47
Q

What is the name of a polymer based on?

A

Its the term poly- followed by the name of the monomer in brackets … e.g poly(styrene)

48
Q

PLEASE LOOK AT PAGE 186 IN THE CHEM BOOK FOR THE GENERAL FORMULA FOR THE ADDITION POLYMERISATION

A

PLEASEE :) <3
OR I WILL STEAL YOUR KNEECAPS
IN UR SLEEP….

49
Q

Give some properties and uses of poly(ethene)

A

properties - flexible, cheap and good insulators

uses- plastic bags, plastic bottles, cling film

50
Q

Give some properties and uses of poly(propene)

A

properties- flexible, does not shatter

uses - buckets, bowls, crates, ropes and carpets

51
Q

Give some properties and uses of poly(chloroethene)

A

properties- tough, good insulator, either hard ot flexible

uses- window frames, gutters, pipes and insulation for wiring

52
Q

Give some properties and uses of poly(tetrafluoroethylene)

A

properties- tough and slippery

uses- non-stick coatings for frying pans, burette taps, stain-proofing clothing

53
Q

What type of polymers is polyester and what process is it made by

A

A synthetic polymer

It is made by condensation polymerisation

54
Q

What is the compound for -esters

A

-COO- (look at a picture of an ester compound)

55
Q

When are esters formed?

A

When carboxylic acid reacts with alcohol in presence of a catalyst - its a condensation reaction as water is also produced

56
Q

What functional groups form a polyester chain

A

The monomers that make up polyester contain alcohol and carboxylic acid functional groups

57
Q

GO TO PAGE 189 FOR THE EQUATION

A

PLEASE, OR THIS TIME I WILL STEAL YOUR ELBOWS

58
Q

Define biodegradable

A

The materials (such as wood and paper) rot because microbes can feed on them and break them down

59
Q

Are synthetic polymers biodegradable?

A

No - it means they last for a long time but they do not rot when they are thrown away

60
Q

What happens to the non-biodegradable rubbish?

A

Some of it is incinerated (burned) and the energy released can be used in electricity but can produce carbon dioxide and possibly toxic substances which can be removed from the waste gases but forms toxic ash which must be disposed of safely

61
Q

How can we reduce the amount of waste that goes into landfills or incinerators?

A

Reduce the amounts of materials we use and also by reusing materials - if an item can be reused any more, it may be possible to recycle it by processing it to make a new item and this will also help to conserve crude oil

62
Q

How much of the UK’s rubbish goes into landfills?

A

Over half

63
Q

State the steps in recycling polymers and making them into new products

A
  • collect the waste
  • sort the waste into different types of polymer (usually done by hand - time consuming)
  • dispose of waste that connot be recycled in a landfill site
  • clean the polymers and grind them into chippings
  • purify the chippings
  • melt the chippings then process them into a new product
64
Q

What system is in place to help with the sorting of polymers?

A

They have codes and symbols on plastic items to show what they are made of

Science - continued (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions