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Flashcards in Unit 2 Deck (46)
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1

How are insouble salts made ?

By the precipitation reaction between 2 solutions

2

How is a salt formed?

When the hydrogen ion is removed from an acid and replaced by a metal ion.

3

What is a fuel ?

A fuel is a substance that burns releasing energy

4

How is a fossil fuel formed (coal)

When trees died and fell into swamp land. A build up of layers over millions of years.

5

How is oil and gas made

The remains of sea creatures and plants died and sunk to the sea bed. Build up of layers over millions of years.

6

What does incomplete combustion produce

Carbon dioxide, water and carbon monoxide

Spot can also be produced

7

What is a homogous

A family of chemical compounds with the same general formula + similar chemical + physical properties

8

What is an alkanes general formula

CnH2n+2

9

What is the general formula for alkenes

CnH2n

10

What is the general formula for cycloalkanes

CnH2n

11

What’s the formula for methyl

CH3

12

What’s the formula for ethyl

C2H5

13

What is the test for saturation

Adding bromine water (brown) to an Alkene will make the solution decolourise rapidly

An alkane takes much longer

14

A hydrocarbon with no c=c is said to be

(Alkanes and cycloalkanes)

Saturated

15

A hydrocarbon with at least 1 c=c is said to be


(Alkenes)

Unsaturated

16

What is an isomer

Molecules which have the same molecular formula but have a different structural formula or


The same number of carbons and hydrogens but a different shape

17

What do alkenes use in Addition reactions

Hydrogen, halogens and water

18

Addition reactions with hydrogen is called

Hydrogenation

19

Addition reactions with halogens form

Dihaloalkanes

20

Addition reactions with water is called

Hydration

21

Addition reactions with water form

Alcohols

22

What are carbohydrates

Compounds that contain the elements carbon, hydrogen and oxygen

23

Do carbohydrates provide energy

Yes

24

What is the test for sugar

Add Benedicts and place in a hot water bath.
If sugar is present then the colour changes from blue to orange.

25

What is the test for starch

Adding iodine to starch produces the colour change from brown to blue/black.

26

What can a carbohydrate be used for

For energy or can be used to produce fuels such as alcohols.

27

What is the equation for fermentation

Glucose ——> ethanol + carbon dioxide

28

What heat is fermentation carried out at

30/40°c

29

What does distilling alcohol do

Removes water and increases the alcohol content

30

What are alcohols also known as

Alkanols