Organic Chemistry

Question 1

How many covalent bonds can carbon form

Answer 1

four covalent bonds

Question 2

What is a hydrocarbon

Answer 2

compound containing only hydrogen and carbon atoms

Question 3

What is combustion

Answer 3

Reaction in which a fuel reacts with oxygen producing oxides and releasing heat

Question 4

What does hydrocarbons and alcohols produce when they burn in a plentiful supply of oxygen

Answer 4

Carbon Dioxide and water

Question 5

What does hydrocarbons and alcohols produce when they burn in a limited supply of oxygen

Answer 5

carbon monoxide and water

Question 6

What type of reactions are hydrocarbons and alcohols burning in a limited or plentiful supply of oxygen

Answer 6

exothermic reactions and give off heat energy

Question 7

how do you test for the products of combustion

Answer 7

Limewater for carbon dioxide
Anhydrous Copper Sulphate to test for water

Question 8

What is the environmental impact of complete combustion for CO2

Answer 8

Hydrocarbons are burnt , carbon dioxide levels in atmosphere are building constantly contributing to global warming because of an increase in greenhouse effect

Question 9

What is the greenhouse effect

Answer 9

Natural process keeping Earth surface warm. Greenhouse gases such as CO2 in atmosphere trap some of the Sun’s radiation keeping Earth at an inhabitable temperature

Question 10

What is global warming

Answer 10

caused by an increase in the greenhouse effect. Came about because of increase in amount of CO2 in atmosphere.
This increase mainly due to burning of fossil fuels.

Question 11

What has global warming caused

Answer 11

A rise in sea levels
Disruption of climate and weather patterns
Changes in crop production
Altered distribution of wild animals and plants

Question 12

Why is hydrogen described as a clean fuel

Answer 12

Hydrogen burns in air to produce water. No Pollutants

Question 13

Why is the incomplete combustion of fuels dangerous

Answer 13

Carbon monoxide is highly toxic to humans
Also colourless and odourless meaning unlikely to be detected unless carbon monoxide has been detected.

Question 14

Why is Carbon Monoxide dangerous to our blood?

Answer 14

Binds to haemoglobin, stronger than O2 but also bonds permanently and so isn’t released which reduces number of red blood cells available to carry O2 round body will steadily decrease, causing tiredness and eventually body will shut down causing death

Question 15

What does acid rain do?

Answer 15

Reacts with metal and rocks such as limestone. Buildings and statues damaged
Damages the waxy layer on leaves of trees and makes it more difficult for trees to absorb minerals they need for healthy growth. May die as result
Makes rivers and lakes too acid for some aquatic life to survive

Question 16

What causes acid rain

Answer 16

Fuels have sulphur impurities in them. When they are burnt, sulphur dioxide is produced
Which then dissolves in rain water causing Acid Rain

Question 17

What is the homologous Series

Answer 17

Family of organic molecules that are very similar

Question 18

How are the homologous Series similar

Answer 18

same general formula
show similar chemical properties
show a gradation in their physical properties
Differ by a CH2 unit

Question 19

What is a Functional Group

Answer 19

Reactive group in a molecule responsible for the characteristic reactions of molecules in that series

Question 20

What is the Functional Group for Alkenes

Answer 20

C=C

Question 21

What is the Functional Group for Alcohols

Answer 21

-OH

Question 22

What is the Functional Group in Carboxylic Acids

Answer 22

-COOH

Question 23

Why are Alkanes less reactive than other organic molecules

Answer 23

They don’t have a functional group.

Question 24

What is the general formula for Alkanes

Answer 24

CnH2n+2

Question 25

What do Alkanes consist of

Answer 25

Carbon Chain Joined by single bonds Hydrogen Molecules bonded to carbon

Question 26

What are the first four alkanes

Answer 26

Methane (CH4) Ethane (C2H6) Propane(C3H8) Butane(C4H10)

Question 27

What chemical class are all Alkanes

Answer 27

Gases

Question 28

How many carbons do Alkanes that are colourless liquids (Petrol) have?

Answer 28

5-15

Question 29

How many carbons do Alkanes that white-waxy solids (decocane) have?

Answer 29

More than 15

Question 30

What is crude oil

Answer 30

Thick, brown liquid which is a mixture of numerous different hydrocarbons which when separated can be solids, liquids or gas

Question 31

Why is Crude Oil described as finite

Answer 31

it will eventually run out

Question 32

Why is fractional distillation used in crude oil

Answer 32

Because they have different boiling points so therefore can be separated through the usage of this method

Question 32

How does fractional distillation work for crude oil?

Answer 32

Fractional distillation occurs in a steel tower called a fractioning tower. Crude oil is first heated in a furnace. The resulting vapours enter the bottom of the tower. The tower is hottest at the bottom and coolest at the top. As the vapours rise, different hydrocarbons condense at different levels based on their boiling points. This process separates the crude oil into various fractions. Small hydrocarbons (with low boiling points) rise to the top. Large hydrocarbons (with high boiling points) condense lower down.

Question 33

Why are alkanes a very useful fuel

Answer 33

when they are burnt they give off a large amount of fuel

Question 34

What colour flame do Alkanes generally burn with

Answer 34

Blue flame As alkanes get bigger the flame they burn with may become yellow and smoky

Question 34

What is an addition reaction in terms of hydrogen

Answer 34

when hydrogen adds across the double bond of alkenes

Question 35

What does an addition reaction do in terms of hydrogen?

Answer 35

Changes alkene into an alkane and needs to be done at 180 degrees with a finely divided Nickel catalyst

Question 36

Why are alkanes described as saturated

Answer 36

Contain no c=c bonds.

Question 37

Why are alkenes described as unsaturated

Answer 37

contain C=C bonds

Question 37

What is an addition reaction in terms of bromine

Answer 37

Bromine can also add across the double bond of alkenes

Question 37

What happens to the colour of bromine in an addition reaction

Answer 37

It goes from reddish/brown bromine water to colourless proving bond is present

Question 38

What are polymers

Answer 38

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

Question 39

What are addition polymers

Answer 39

A polymer formed when monomers add together and produces no other substance, other than the polymer, is called an addition polymer.

Question 40

What is polymerisation

Answer 40

process of creating a long chain molecule from small molecules

Question 40

What is addition polymerisation

Answer 40

Addition polymerisation occurs when small molecules join together to form long chain molecule called polymers

Question 40

What is Polythenes properties

Answer 40

Light flexible resistant to attack by acids

Question 40

Polythenes uses

Answer 40

Cling film Plastic bags Bottles Buckets and basins

Question 40

How is Polythene made

Answer 40

from ethene

Question 40

How is PVC made

Answer 40

From chlorothene

Question 41

What are the properties of PVC

Answer 41

Tough Good Durable Waterproof Insulator

Question 42

Uses of PVC

Answer 42

Electric Cables Guttering Drain Pipes Umbrellas

Question 43

What is cracking

Answer 43

Cracking breaks down large saturated hydrocarbons (alkanes) into smaller, more useful ones. Some products are unsaturated hydrocarbons (alkenes). Fractional distillation produces some less useful fractions with low demand. Large hydrocarbons are inefficient fuels—hard to ignite and poor flow. Cracking improves usefulness by making smaller, more efficient molecules. Process involves heating to vaporise large molecules. Vapours are passed over a hot catalyst or mixed with steam and heated. Causes thermal decomposition, breaking chemical bonds. Produces smaller alkanes (fuels) and alkenes (used in plastics).

Question 44

What general formula do Alcohols have

Answer 44

CnH2n+1OH

Question 45

What functional group do Alcohols have

Answer 45

-OH

Question 46

How can Alcohols be produced through addition?

Answer 46

Can be produced from alkenes. Water adds on across the double band, similar to reaction with bromine

Question 47

Production of Alcohols by addition formula

Answer 47

Ethene + Steam = Ethanol C2H4 (g) + H20 (g) = C2H5OH (g)

Question 48

How is alcohols produced through fermentation

Answer 48

If yeast is added to sugar or starch solution and the mixture is left in a warm place enzymes in the yeast convert the sugar or starch to form alcohol and CO2

Question 49

What colour flame do alcohols burn with

Answer 49

Blue flame

Question 50

What is the carboxylic acids general formula

Answer 50

CnH2n+1COOH

Question 51

What is the Carboxylic acids functional group

Answer 51

-COOH

Question 52

What does an acid form when they react with a base

Answer 52

Form soalt and water

Question 53

What does an acid form when they react with a carbonate

Answer 53

Salt, water and carbon dioxide

Question 54

What does an acid form when they react with a metal

Answer 54

Salt and hydrogen

Question 55

What is a molecular formula

Answer 55

Actual number of atoms in each element

Question 56

What is an empirical formula

Answer 56

Simplest whole number ratio of the atoms of each element in a compound

Question 57

What is a general formula

Answer 57

Type of empirical formula that represents the composition of any member of a particular homologous series

Question 58

What is a structural formula

Answer 58

Shows arrangement of atoms in a molecule and uses lines to show covalent bonds which join atoms together