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Flashcards in Alkanes Deck (39):
0

What words (sentence) do we use to remember the names of the Alkanes in order?

My (Methane), elephant (Ethane), prefers (propane), bananas (Butane), peeled (pentane).

1

What is the general formulae for an Alkanes ?

CnH2n+2

2

Alkanes are an .......series?

Homologous series of saturated hydrocarbons.

3

Homologous series is a series if compounds which; (4)

-have the same general formula
-have the same chemical properties
-have the same physical properties which increase up the series
-differ from their nearest neighbour in molecular formula by a constant amount, CH2

4

What is a hydrocarbon?

A compound made up of carbon and Hydrogen only.

5

What is the definition of Saturated?

Only contains single bonds

6

What does the boiling point do as the carbon chain increases?

Increases

7

All Alkanes burn in excess oxygen to form.....? (2 substances)

Carbon dioxide and Water

8

What is a STRUCTURAL ISOMERISM?

2 or more compounds which have
- the same molecular formula
-different structural formula

9

Combustion

When Alkanes burn in excess of oxygen they give out large amounts of HEAT ENERGY hence they make good fuels.

10

What are the products of the combustion of Alkanes?

Carbon dioxide
Water

11

What is the equation for the combustion of Alkanes?

...............+Oxygen=Carbon Dioxide+Water

12

What are the observations when Alkanes react with halogens?

-2 layers form
-orange layer SLOWLY goes colourless

13

What is the equation for complete combustion?

Alkanes (Hydrocarbon)+excess oxygen= carbon dioxide + water

14

If there is a LIMITED SUPPLY OF EXYGEN what is the equation for the complete combustion?

Alkanes+limited supply if oxygen = carbon monoxide +water

15

What three words go with CARBON MONOXIDE that all end in 's'...!!!!!!

Colourless
Odourless
Poisonous

16

In which 3 scenarios does INCOMPLETE COMBUSTION take place?

-car engines
-boiler in a poorly ventilated situation
-Calourgas heater in a poorly ventilated room

17

What is the equation for cracking?!!!!

Heat
Long chain alkane >short chain+alkene. Catalyst

18

What are Alkanes used for

Making plastic

19

What are short chain Alkanes used for?

Used as fuels

20

What fractions are usually cracked?

Long chain or medium chain hydrocarbons

21

What are polymers?

Long chain molecules which are mad when small molecules Called Momomers are added together.

22

Unsaturated Alkanes with carbon-carbon double bonds can act as....??

Monomers

23

When monomers are heated up with an "initiator" and put under high pressure what happens to form a polymer?

The double bonds open up to form a very long chain of single bonded carbon atoms. ADDITION POLYMERISATION

24

What is the repeating pattern if atoms along the polymer chain called?

Repeating unit

25

What do the properties of the polymer depend upon? (3)

-The monomer it's made from
-The conditions it's made under
-Whether or not it has cross links

26

Whey comes as a result of polymer chains not all being the same length?

It's physical properties are more of mixture.

27

How many isomers does propene have?

NONE!!!!!!

28

What are the properties of polyethene/ethene? (4)

-low density form LDPE
-Very flexible light but not very strong

-high density form HDPE
-Light and strong/more ridged

29

Uses of Ethene/polyethene? (2)

-plastic shopping bags
-drink Bottles, Buckets and Bowls

30

What are the properties of propene/polypropene? (1)

Very tough and strong

31

What uses does propene/polypropene have? (3)

Crates
Ropes
Carpets

32

What are the properties of chloroethene (vinyl chloride)/polychloroethene (PVC)? (2)

-Ridged and very waterproof
-very resistant to chemicals

33

What are the uses of chloroethene (vinyl chloride)/polychloroethene (PVC)? (2)

-wellies
-credit cards
-gutters bad drain pipes
-window frames
-insulating coating for electrical wires

34

What are the properties of phenylethene (styrene)/polystyrene (PS)? (1)

Hard and brittle but can be expanded with gas

35

What are the uses of phenylethene (styrene)/polystyrene (PS)? (4)

-Foam packaging
-cups
-fast food cartons
-electrical insulation

36

What's a monomer?

Small molecule with a double bond
e.g. C=C

37

What does UNSATURATED mean?

A compound contains a DOUBKE BOND.

38

What's the general formulae for Alkenes?

CnH2n