4- Organic Chemistry❗️

Question 1

What is the general formula for alkanes?

Answer 1

CnH2n+2

Question 2

List the first five alkanes

Answer 2

Methane 
Ethane 
propane 
butane
 pentane

Question 3

Why are alkanes saturated?

Answer 3

There are only single bonds between the carbon atoms

Question 4

Why are alkenes unsaturated molecules?

Answer 4

They contain a double bond between two of the carbon atoms in a chain

Question 5

What is the general formula for alkenes?

Answer 5

CnH2n

Question 6

List the first alkenes

Answer 6

Ethene
propene
Butene

Question 7

How do you test for alkanes and alkenes?

Answer 7

Using bromine water to test saturation

Question 8

What colour does bromine go when added to saturated alkanes?

Answer 8

Stays orange

Question 9

What colour does bromine go when added to unsaturated alkenes?

Answer 9

Turns colourless

Question 10

What is the general formula of an alcohol

Answer 10

CnH2n+1OH

Question 11

What is the functional group of alcohols?

Answer 11

-OH

Question 12

Name the first 4 alcohols?

Answer 12

Methanol
ethanol
propanol
butanol

Question 13

What do alcohols form when oxidised?

Answer 13

Carboxylic acids

Question 14

What is the word equation for complete combustion?

Answer 14

Hydrocarbon + oxygen —> carbon dioxide + water

Question 15

When does complete combustion happen?

Answer 15

When there is plenty of oxygen

Question 16

What does incomplete combustion produce?

Answer 16

Carbon Dioxide
water
carbon monoxide

Question 17

When does incomplete combustion happen?

Answer 17

When there is not enough oxygen

Question 18

How does acid rain form?

Answer 18

sulphur dioxide + nitrogen oxides mix with water vapour in clouds they form dilute sulphuric + nitric acid

Question 19

What’s the equation for production of ethanol through steam?

Answer 19

phosphoric acid

Ethanol + steam —————————> ethanol

Question 20

What is fermentation?

Answer 20

When sugar is converted into ethanol using yeast

Question 21

Give the equation for fermentation

Answer 21

Glucose—> ethanol + carbon dioxide

Question 22

Top of column

Answer 22

Short chain

Question 23

What do homologous series have in common?

Answer 23

• same general formula
• same functional group
• similar chemical properties

Question 24

What are isomers ?

Answer 24

compounds with the same molecular formula but different displayed formula

Question 25

What is bitumen used for ?

Answer 25

Surfacing roads + roofs

Question 26

What is kerosene used for?

Answer 26

Jet fuel

Question 27

What is fuel oil used for?

Answer 27

Ships + power stations

Question 28

What is liquified petroleum gas used for?

Answer 28

Domestic heating + cooking

Question 29

Describe properties of short chain molecules

Answer 29

- less viscous - more flammable - lower boiling points - more volatile

Question 30

Describe properties of long chain molecules

Answer 30

- more viscous - less flammable - higher boiling points - less volatile

Question 31

What is the definition of cracking?

Answer 31

The thermal decomposition of long chain hydrocarbons into shorter more useful ones

Question 32

Hydrocarbon + oxygen —>

Answer 32

Carbon dioxide + water

Question 33

What kind of reactions do all alkenes undergo?

Answer 33

Addition reactions

Question 34

What can alkanes react with?

Answer 34

Bromine (need UV light) - substitution reaction