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Flashcards in Unit 2 Deck (48):
0

What is a fuel?

A fuel is a substance that has stored energy, which it releases when it burns

1

What is a fossil fuel?

Decayed and fossilised remains of animals and plants that one lived millions of years ago

2

What are the three main types or fossil fuels?

Coal, Oil and Gas

3

Describe how coal is formed

Fallen trees were covered with layers of mud and earth and they were gradually broken down and compressed which eventually formed coal

4

Describe how oil and natural gas are formed

Dead microscopic creatures that sank to the bottom of the sea bed were covered with layers of sand which helped to turn them into oil and natural gas

5

A colourless liquid formed in a test tube. How could you prove that this liquid was pure water?

It will boil at 100 degrees and freeze at 0 degrees

6

What is complete combustion?

Complete combustion occurs when there is enough oxygen to completely burn all the carbon and hydrogen in a fuel

Hydrocarbon + oxygen ➡️ carbon dioxide + water

7

What is incomplete combustion?

Incomplete combustion occurs when there is an insufficient supply of oxygen to allow complete combustion

Hydrocarbon + oxygen ➡️ carbon monoxide + carbon (soot) + water

8

What elements are present in hydrocarbons?

Hydrogen and Carbon

9

Ionic

High melting point and only conducts as a liquid

10

Covalent Network

High melting point never conducts

11

Covalent Molecular

Low melting point and never conducts

12

Metallic

High melting point and always conducts

13

What is the general formula for the alkanes?

C H
n 2n + 2

14

How many bonds does a carbon atom need to have?

4

15

What is the formula and full structural formula for methane?

H
H-C-H CH
H 4

16

What is the formula and full structural formula for ethane?

C H H H
2 6 H -C - C - H
H H

17

What is the formula and full structural formula for propane?

C H H H H
3 8 H - C - C - C - H
H H H

18

What is a homologous series?

A homologous series is a group of chemicals with similar chemical properties, gradually changing physical properties and a general formula

19

What is the general formula for the alkenes?

C H
n 2n

20

What is the first member of the alkene family's?

Ethene

21

Why is there no alkene with one carbon atom?

Because there needs to be at least two carbon atoms to have a double bond

22

What is the molecular and full structural formula for Ethene?

C H H H
2 4 H - C = C - H

23

What is the molecular and full structural formula for Butene?

C H H H H H
4 8 H - C - C = C - C - H
H H

24

What is meant by saturated?

Alkenes are described as saturated molecules because they cannot add on any extra hydrogen atoms

25

What is meant by unsaturated?

Alkenes are described as unsaturated molecules because they can add on extra hydrogen atoms since they have a double bond

26

What is the addition reaction between propane and bromine?

H H H H H H
H - C - C = C - H + Br - Br ➡️ H - C - C - C - H
H H Br Br
Propene Bromine 1,2-dibromopropane
(Colourless) (Orange) (Colourless)

27

What is the general formula for the cycloalkanes?

C H
n 2n

28

What is the first member of the cycloalkanes and what is the molecular and full structural formula?

C H H H
3 6 C
H - C C - H
H H

29

Complete this cracking equation:

C H ➡️ C H + ______
16 34 9 18

C H ➡️ C H + C H
16 34 9 18 7 16

30

Complete this cracking equation:

_____ ➡️ C H + C H
4 8 5 12

C H ➡️ C H + C H
9 20 4 8 5 12

31

Give the systematic name for this hydrocarbon:

CH - CH - CH CH CH
3 CH 2 2 3
3

2-methylpentane

32

Give the systematic name for this hydrocarbon:
CH
3
CH - CH - C - H
CH
2
CH
3

3-methylpentane

33

What is the general formula for the alcohols (alkanols)?

C H OH
n 2n + 1

34

What is the molecular, full structural and shortened structural formula for ethanol?

C H OH
2 5
H H
H - C - C - O - H
H H

CH CH OH
3 2

35

What is the molecular, full structural and shortened structural formula for butanol?

C H OH
4 9
H H H H
H - C - C - C - C - O - H
H H H H

CH CH CH CH OH
3 2 2 2

36

Give the systematic name for this alkanol:

CH - CH - CH - CH
3 OH 2 3

butan-2-ol

37

Give the systematic name for this alkanol:

CH - CH - CH - CH - CH - CH - CH
3 2 2 2 OH 2 3

heptan-3-ol

38

Hat is the general formula for the carboxilic acids (alkanoic acids)?

C H O
n 2n 2

39

What is the molecular, full structural and shortened structural formula for butanoic acid?

C H O
4 8 2
H H H = O
H - C - C - C - C
H H H O - H

CH CH CH COOH
3 2 2

40

What is an ester?

An ester is the product of the reaction between a carboxilic (alkanoic) acid and an alkanol

41

Name the ester which is formed when propanol reacts with ethanoic acid and draw the full structural formula for both reactants and products

H H H O = H H H H = O H
H - C - C - C - O - H + C - C - H ➡️ H - C - C - C - O - C - C - H
H H H H - O H H H H
+ H O
2
propanol + ethanoic acid ➡️ propyl ethanoate + water

42

In what two ways do you know that an ester has been formed?

Oily layer and a characteristic smell

43

What are some uses of esters?

Perfumes and food flavourings

44

What mass of carbon dioxide is produced when 64g of methane is burned completely in oxygen?

CH + 2O ➡️ CO + 2H O
4 2 2 2
1 2 1 2
Mole Moles Mole Moles

176g

45

Calculate the mass of ethanol which would require to be completely burned to produce 3.6g of water

C H OH + 3O ➡️ 2CO + 3H O
2 5 2 2 2

3.07g

46

The temperature of 50cm3 of water is increased by 15 degrees

3.14kJ

47

The temperature of 500cm3 of water is increased by 8.6 degrees

18kJ