Organic Chemistry 2

Question 1

Define polymerisation

Answer 1

The process of creating/producing a long chain of molecules from small molecules

Question 2

Define addition polymerisation

Answer 2

How monomers can join together to form very long chain molecules called polymers

Question 3

Define monomer

Answer 3

The small molecules that add together to make a polymer are called monomers. These are alkenes

Question 4

What is a polymer

Answer 4

Large organic molecules formed when smaller molecules join together in long chains.

Question 5

What are the properties of polythene

Answer 5

Light, flexible and resistant to attack by acids and alkalis

Question 6

What are the uses of polythene

Answer 6

Cling film, plastic bags, bottles, buckets and basins

Question 7

Properties of PVC

Answer 7

Tough, durable, waterproof and a good insulator

Question 8

Uses of PVC

Answer 8

Electric cables, guttering, drain pipes, umbrellas and window frames

Question 9

What are the benefits of plastics

Answer 9

Less dense than other materials
Resistant to chemicals and water
Excellent insulator properties
Extremely long lasting
Inexpensive

Question 10

What are disadvantages of plastics

Answer 10

Addition polymers are non-biodegradable (not decomposed by bacteria in the environment)
Surplus of plastics littering our oceans
Kills aquatic life

Question 11

What are the advantages of landfill

Answer 11

Cheap and easy
Local treatment so less transport needed
Land can be reused after

Question 12

What are the disadvantages of landfill

Answer 12

Wastes land
Takes a long time to break down
Polluting gases released

Question 13

What are the advantages of incineration

Answer 13

Heat energy can generate electricity
Less waste going to landfill

Question 14

What are the disadvantages of incineration

Answer 14

Releases polluting gases
Ash residue is toxic
Costly to build and maintain

Question 15

What is the general formula of alcohol

Answer 15

CnH(2n+1)OH

Question 16

What are the 4 alcohols you need to know

Answer 16

Methanol
Ethanol
Propan-1-ol
Propan-2-ol

Question 17

What is the molecular formula of methanol

Answer 17

CH3OH

Question 18

What is the molecular formula of ethanol

Answer 18

C2H5OH

Question 19

What is the molecular formula for propan-1-ol and propan-2-ol

Answer 19

C3H7OH

Question 20

What are the observations for the combustion of alcohol

Answer 20

A clean blue flame and heat is released

Question 21

What is the equation for the complete combustion of alcohol

Answer 21

Alcohol + oxygen —> carbon dioxide + water

Question 22

What is the equation for the incomplete combustion of alcohol

Answer 22

Alcohol + oxygen —> carbon monoxide + water

Question 23

How is alcohol produced using fermentation

Answer 23

A sugar solution is mixed with yeast in warm conditions in the absence of oxygen. The reaction produces carbon dioxide and ethanol. The reaction is brought about by the enzyme, zymase which is presents in yeast.

Question 24

What is the equation for fermentation

Answer 24

Glucose —> carbon dioxide + ethanol
(Enzyme in yeast)

Question 25

How else can ethanol be produced

Answer 25

Hydration of Ethene with steam. (Hydration reaction)

Question 26

What is the equation of the hydration of Ethene with steam to produce ethanol

Answer 26

Ethene + water (steam) —> ethanol (Phosphoric acid catalyst)

Question 27

What happens when alcohols are oxidised by air

Answer 27

Mild oxidisation which will form carboxylic acids. E.g if wine is left standing it will be oxidised to ethanoic acid by the oxygen and the wine is turned into wine vinegar. Vinegar is a solution of ethanoic acid

Question 28

How are alcohols oxidised by acidified potassium dichromate

Answer 28

Acidified potassium dichromate solution is an oxidising agent which oxidises some alcohols to carboxylic acids on warming

Question 29

What observations can be seen when acidified potassium dichromate solution reacts with alcohols

Answer 29

The acidified potassium dichromate changes from orange to green when it oxidise alcohols

Question 30

What is the general formula for carboxylic acids

Answer 30

CnH(2n+1)COOH

Question 31

What are the 4 carboxylic acids you need to know

Answer 31

Methanoic acid Ethanoic acid Propanoic acid Butanoic acid

Question 32

What is the molecular formula of methanoic acid

Answer 32

HCOOH

Question 33

What is the formula for ethanoic acid

Answer 33

CH3COOH

Question 34

What is the formula for propanoic acid

Answer 34

C2H5COOH

Question 35

What is the molecular formula for butanoic acid

Answer 35

C3H7COOH

Question 36

Why are carboxylic acids weak acids

Answer 36

They only partially ionise in water

Question 37

What are the observations when carboxylic acids react with sodium carbonate

Answer 37

Bubbles of gas formed, the white solid disappears and a colourless solution is formed

Question 38

What is the general equation for carboxylic acid reacting with sodium carbonate

Answer 38

Carboxylic acid + sodium carbonate —> sodium salt + water + carbon dioxide

Question 39

How can a carboxylic acid be distinguished from other organic compounds

Answer 39

Only carboxylic acids will release carbon dioxide when sodium carbonate is added to a sample. Gas can be identified by bubbling it through limewater and solution turning milky white.

Question 40

What are the observations when a carboxylic acid reacts with magnesium

Answer 40

Bubble of gas are produced, heat is released, the grey solid disappears and a colourless solution is formed

Question 41

What is the general equation for when carboxylic acids react with magnesium

Answer 41

Carboxylic acid + magnesium —> magnesium salt + hydrogen

Question 42

What can be observed when carboxylic acid reacts with sodium hydroxide

Answer 42

Heat is released and the solution remains colourless

Question 43

What is the general equation for carboxylic acids reacting with sodium hydroxide

Answer 43

Carboxylic acid + sodium hydroxide —> sodium salt + water

Question 44

How are alkanes differentiated from other organic compounds

Answer 44

When reacted with bromine water it will change from orange/brown to colourless

Question 45

Name common atmospheric pollutants

Answer 45

Carbon dioxide Carbon monoxide Soot (carbon particles) Sulfur dioxide leading to acid rain

Question 46

How is carbon dioxide formed and what problems can it cause?

Answer 46

Caused by complete combustion of hydrocarbon fuels. CO2 is a greenhouse gas and leads to the greenhouse effect. Absorbs infrared radiation given off by the earth and causes the earths surface to warm leading to: Sea level rises Flooding Climate change

Question 47

How is carbon monoxide formed and what are the problems it can cause

Answer 47

Formed by incomplete combustion of fuels Carbon monoxide is a toxic gas as it combines with haemoglobin in the blood, reducing its capacity to carry oxygen.

Question 48

How is soot formed and what problems does it cause

Answer 48

Formed by incomplete combustion of fuels The carbon particles pollute the air and can cause lung damage and respiratory problems

Question 49

How is sulfur dioxide formed and what problems can it cause

Answer 49

Many fuels contain sulfur impurities which burn and produce acidic sulfur dioxide. The sulfur dioxide reacts with water in the atmosphere to form sulfurous acid which falls as acid rain Acid rain can: Damage buildings especially ones made of limestone Damage vegetation Kills fish in lakes and rivers