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Flashcards in C14. Organic chemistry Deck (29)
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1

What do all organic compounds contain?

Carbon
Usually hydrogen as well.

2

What types of fossil fuels product carbon dioxide on combustion?

Coal, natural gas and petroleum.

3

What process separates petroleum into different fractions?

Fractional distillation.

4

What is the main constituent of gas?

Methane

5

What does petroleum consist of?

A mixture of hydrocarbons - carbon and hydrogen atoms.

6

How does fractional distillation work?

Separates the hydrocarbons using the difference in their boiling points.

7

State the trends of petroleum distillation.

1. Down = the boiling points increase (temp increases)
2. Down = the size of molecules is larger.
3. Down = density increases.
4. Down = flammability increases.

8

State the use and temperature range of 'refinery gas'.

Bottled as gas for heating and cooking.
Under 40C.

9

State the use and temperature range of 'gasoline' (petrol).

Fuel for cars (petrol).
40 - 100C.

10

State the use and temperature range of 'naphtha'.

Making chemicals, especially plastics.
80 - 180C.

11

State the use and temperature range of 'kerosene' (paraffin).

Fuel for jet aircraft and heating.
160 - 250C.

12

State the use and temperature range of 'diesel oil'.

Fuel for lorries and tractors.
250 - 300C.

13

State the use and temperature range of 'fuel oil'

Fuel for power stations, ships and home heating.
350 - 500C

14

State the components and the uses of 'residue'.

Lubricating oil - lubricants, waxes and polishes.
Bitumen - making road surfaces and sealing roofs.

15

Name the characteristics of 'alkanes'.

- Hydrocarbons
- Compounds of carbon and hydrogen only
- Single bonds (saturated)
- E.g. Methane, Ethane, Propane, Butane
- Not very reactive but they burn well
- Ends in -ane

16

Name the characteristics of 'alkenes'.

- Hydrocarbons
- Carbon and hydrogen only
- Have a double bond between two of the carbons (unsaturated)
- E.g. Ethene, Propene etc.
- Ends in -ene

17

Name the characteristics of 'alchohol'.

- Like alkanes
- One of the hydrogen atoms is replaced by OH
- E.g. Ethanol
- Ends in -ol

18

What is a homologous series?

A group of compounds with the same functional group.
- Similar properties

19

What is the formula for 'alkanes'?

C(n)H(2n+2)

20

What is the formula for 'alkenes'?

C(n)H(2n)

21

What is the formula for 'alcohols'?

C(n)H(2n-1)OH

22

What is the formula for 'acids'?

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

23

What are the differences between homologous series?

- Chain length
- Physical properties gradually change due to increasing molecule size

24

How do we form ethanol?

Fermentation - enzymes in yeast cells break down glucose to carbon dioxide and ethanol (exothermic)
From alkenes by addition of steam
C(6)H(12)O(6) -> 2C(2)H(5)OH + 2CO(2)

25

What is another way of obtaining ethanol in a chemical factory?

Addition of the catalyst steam to ethene.

26

Describe the combustion of ethanol.

Burns in oxygen to form carbon dioxide and water.
C(2)H(5)OH + 3O(2) -> 3H(2)O + 2CO(2)

27

What the uses of ethanol?

As a fuel + solvent (dissolves many things and evaporates easily)

28

Why is ethanol a better fuel than petrol?

It has already has an oxygen molecule in it.

29

How do manufacture alkene?

Alkanes -> alkenes
- Heat alkane in the presence of a catalyst -> molecule breaks down