Hydrocarbons

Question 1

A hydrocarbon is…

Answer 1

….a compound containing ONLY hydrogen and carbon

Question 2

A homologous series is…

Answer 2

….a family of compounds with the SAME GENERAL FORMULA and SIMILAR CHEMICAL PROPERTIES

Question 3

The first member of the ALKANES is…

Answer 3

Methane

Question 4

The general formula for the alkanes is…

Answer 4

CnH2n+2

Question 5

methane, ethane,________, butane

Answer 5

propane

Question 6

methane + oxygen –> ? + ?

Answer 6

carbon dioxide + water

Question 7

A functional group is…..

Answer 7

…the part of a molecule which gives the molecule its chemical properties

Question 8

The homologous series containing a carbon carbon DOUBLE bond are the…

Answer 8

…alkenes

Question 9

The general formula for the alkenes is…

Answer 9

…CnH2n

Question 10

The alkene with six carbon atoms, where the C=C is between the first two carbons is called..

Answer 10

…hex-1-ene

Question 11

A hydrocarbon containing a C=C is known as an u____________ hydrocarbon

Answer 11

unsaturated

Question 12

To distinguish between a saturated and an unsaturated hydrocarbon we can add it to……

Answer 12

…bromine solution

Question 13

When an alkene is added to bromine solution it….

Answer 13

…decolourises the solution (goes from orange->colourless)

Question 14

Which other homologous series have the same general formula as the alkenes?

Answer 14

cycloalkanes

Question 15

The cycloalkane with five carbon atoms is called…

Answer 15

..cyclopentane

Question 16

Which will have the higher boiling point, ethane or hexane?

Answer 16

hexane

Question 17

Why does octane have a higher boiling point than pentane?

Answer 17

Larger molecules have higher boiling points as there are stronger INTERMOLECULAR FORCES (attractions between molecules)

Question 18

Isomers are…

Answer 18

…molecules with the same molecular formula but a different structural formula

Question 19

The type of reaction where a small molecule adds across the double bond in an alkene is called an _____________ reaction

Answer 19

addition

Question 20

The molecule produced when bromine undergoes and addition reaction with ethene is called..

Answer 20

..1,2-dibromoethane

Question 21

When an alkene reacts with hydrogen, the product is an….

Answer 21

..alkane

Question 22

Adding hydrogen across a double bond is called….

Answer 22

…hydrogenation

Question 23

When water is added across a double bond in an alkene, the product is an…

Answer 23

…alcohol

Question 24

The OH functional group in an alcohol is called a ___________ group

Answer 24

hydroxyl

Question 25

Alcohols are often used as .....

Answer 25

..fuels and solvents

Question 26

The general formula for the alcohols is..

Answer 26

CnH2n+1 OH

Question 27

The alcohol with five carbon atoms where the OH group is on carbon 3 would be called

Answer 27

pentan-3-ol

Question 28

ethanol + oxygen--> ? + ?

Answer 28

carbon dioxide + water

Question 29

Which will have a higher boiling point and why..methanol or pentanol?

Answer 29

Pentanol will have higher b.pt as it is larger and will have stronger INTERMOLECULAR forces

Question 30

Carboxylic acids contain a functional group COOH. This is called the____________ group

Answer 30

carboxyl

Question 31

The carboxylic acid containing seven carbon atoms will be called..

Answer 31

..heptanoic acid

Question 32

A carboxylic acid will have a pH ......

Answer 32

..below 7

Question 33

An exothermic reaction is one which...

Answer 33

...releases heat energy

Question 34

A reaction which takes in heat energy is known as an_____________ reaction

Answer 34

endothermic

Question 35

In a combustion reaction something combines with ____________

Answer 35

oxygen

Question 36

Hexene has an isomer which is not an alkene. This isomer is.....

Answer 36

cyclohexane