✅Chemistry PAPER2 organic chemistry

Question 1

What is a hydrocarbon

Answer 1

hydrocarbons are compounds formed from carbon and hydrogen atoms

Question 2

What are alkanes

Answer 2

A type of hydrocarbon

Question 3

What are the first four alkanes

Answer 3

Methane, Ethan, propane, butane

Question 4

What is crude oil

Answer 4

it is a finite resource and a fossil fuel found in rocks

Question 5

Why is crude oil important

Answer 5

It is an important source of raw materials

Question 6

What is the chemical formula for methane

Answer 6

CH4

Question 7

What is the chemical formula for Ethane

Answer 7

C2H6

Question 8

What is the chemical formula for propane

Answer 8

C3H8

Question 9

What is the chemical formula for butane

Answer 9

C4H10

Question 10

What are examples of fossil fuels

Answer 10

Coal oil gas

Question 11

What can crude oil be used for

Answer 11

Provides fuels for transport for example cars, diesel oil heavy fuel oil LPG these all come from crude oil

Question 12

What are petrochemicals

Answer 12

Petrochemicals are compounds that come from crude oil

Question 13

What do the petrochemical industry use some of the compounds from crude oil for

Answer 13

Polymers, solvent, lubricant, detergent

Question 14

What method is used to separate crude oil

Answer 14

Fractional distillation

Question 15

What does saturated mean

Answer 15

It has too many and it can’t have anymore

Question 16

How many hydrogens will an alkane have with 10 carbons

Answer 16

4 hydrogens

Question 17

What can crude oil be used to make

Answer 17

Fuels, plastics

Question 18

What is the chemical that makes crude oil

Answer 18

Hydrocarbon

Question 19

What are organic compounds

Answer 19

Compounds that are containing carbon atoms

Question 20

What do carbon atoms bond together to form

Answer 20

Different groups called homologous series

Question 21

What do the Homologous series groups contain

Answer 21

Similar compounds for example alkanes and alkenes

Question 22

What is crude oil formed from

Answer 22

The remains of plankton as well as other animals and plants that died millions of years ago

Question 23

What is plankton

Answer 23

Plankton is made up of tiny living plants and animals which float around in the ocean and waters

Question 24

What is an alkane

Answer 24

A saturated hydrocarbon for example methane

Question 25

What is an alkene

Answer 25

An unsaturated hydrocarbon which contains a carbon-carbon double bond for example ethene

Question 26

How can you tell if a molecule is an alkane or alkene

Answer 26

If it is an alkane they will only have a single carbon bond but if it is an alkene they will have a double carbon bond

Question 27

What is fractional distillation

Answer 27

When compounds are separated in a mixture

Question 28

How does fractional distillation work

Answer 28

Oil is heated until most of it has evaporated, the gases then enter a fractionating column, liquid is then drained off

Question 29

Why do shorter hydrocarbons have low boiling points

Answer 29

Because they are still gases at low temperature so they don’t condense and turn back into liquid until they move up the top of the column

Question 30

Why do longer hydrocarbons have higher boiling points

Answer 30

Because they’ll only stay gas if very hot so as they move up the column it gets cooler so they can condense back into liquids and drain out of the column earlier when they’re near the bottom

Question 31

What is cracking

Answer 31

Cracking means to split up long chain hydrocarbons

Question 32

What is the process called when longer alkane molecules are turned into smaller more useful ones

Answer 32

Cracking

Question 33

Cracking is a thermal decomposition reaction what does this mean

Answer 33

This means the molecules are broken down by heating them, this can be done by catalytic cracking or by steam cracking

Question 34

Why is there a high demand for fuels with small molecules

Answer 34

Because short chain hydrocarbons tend to be more useful than a long chain hydrocarbons

Question 35

How does steam cracking happen

Answer 35

Long chain hydrocarbons are heated to turn them into a gas, the hydrocarbon vapour is mixed with steam, they are then heated to a very high temperature which split them into smaller molecules

Question 36

How does catalytic cracking happen

Answer 36

Long chain hydrocarbons are heated to turn them into gas then the vapours Passover hot powdered aluminium oxide catalyst, the long chain molecule split apart on the surface of the specs of catalyst

Question 37

When does complete combustion occur

Answer 37

When there is plenty of oxygen

Question 38

What is the chemical formula for complete combustion

Answer 38

Hydrogen + oxygen = Co2 + water + energy

Question 39

What is combustion

Answer 39

A chemical process or reaction between hydrocarbons and oxygen

Question 40

What happens during combustion

Answer 40

During combustion both carbon and hydrogen form the hydrocarbon are oxidised, oxidation is the gain of oxygen

Question 41

What is the word equation for the complete combustion of an alkane

Answer 41

Alkane + oxygen = Co2 + water

Question 42

How can you tell if hydrocarbons are alkanes

Answer 42

You times it by two and add two

Question 43

What four substances that are fuel made from crude oil

Answer 43

Diesel oil, petrol, liquefied petroleum gas (LPG) kerosene

Question 44

Name two types of hydrocarbons are produced as a result of cracking

Answer 44

Alkanes, Alkenes

Question 45

State one way on how catalytic cracking is different from steam cracking

Answer 45

The vapour is mixed in steam cracking, but in catalytic the vapour is passed

Question 46

What happen to the evaporated crude oil within the fractionating column

Answer 46

It cools and condenses

Question 47

what are the differences in longer hydrocarbon chains and shorter hydrocarbon chains

Answer 47

longer chains – higher boiling point, only stays gas if hot, less flammable, condenses at the bottom which is hotter shorter chains, lower boiling point, only stays a gas if cool, extremely flammable, condenses at the top which is cooler