CHEMISTRY - Crude Oil, Fuels and Organic Chemistry

Question 1

what is crude oil

Answer 1

a fossil fuel formed over millions of years from the remains of dead marine organisms. it is non renewable and a finite source

Question 2

what is fractional distilation

Answer 2

a process that is used to separate pure liquid from a mixture of liquids with different boiling points.

Question 3

how are the two liquids separated in fractional distillation

Answer 3

separated based on different boiling points

Question 4

how is crude oil separated using fractional distillation.

Answer 4

-crude oil is pumped in as vapour at the bottom of the fractionating column
-the column gets cooler towards the top
-as vapours rise they re-condense back to liquids at different heights, and they are pumped out.
-each liquid is called a fraction
-a fraction is a mixture of hydrocarbons of similar size, with similar boiling points.

Question 5

what are the main uses for liquid petroleum gas

Answer 5

gas for cookers

Question 6

what is the main use of petrol

Answer 6

fuel for cars

Question 7

what is the main use of paraffin/kerosene

Answer 7

fuel for jets

Question 8

what is the main use of diesel

Answer 8

fuel for cars/heavy vehicles

Question 9

main use of heating oil

Answer 9

fuel for central heating systems

Question 10

main use of fuel oil

Answer 10

fuel for ships

Question 11

main use of bitumen

Answer 11

‘tar’ for surfacing roads

Question 12

what is a hydro carbon

Answer 12

compound made with only hydrogen and carbon

Question 13

what are the political issues of crude oil exploitation

Answer 13

its a finite source so our own supplies will eventually run out. then the uk will depend on politically unstable countries. supplies will be scarce.

Question 14

what are the environmental issues of crude oil exploitation

Answer 14

crude oil can be spilled during transport by ship, causing oil slicks that damage beaches and wildlife.

Question 15

why is crude oil a non renewable source

Answer 15

it is used up faster than its formed.

Question 16

what is the equation for complete combustion

Answer 16

hydrocarbon + oxygen –> carbon dioxide + water

Question 17

what substance is cobalt chloride paper used to test for

Answer 17

water vapour

Question 18

describe the colour change seen when the products of complete combustion are passed over cobalt chloride paper

Answer 18

goes from blue to purple

Question 19

what substance is limewater used to test for

Answer 19

CO2
carbon dioxide

Question 20

describe what is observed when the products of complete combustion are bubbled through limewater

Answer 20

goes milky

Question 21

how is hydrogen used as a rocket fuel

Answer 21

oxygen will violently react with pure hydrogen, the hydrogen burns with the oxygen to form water and heat.

2 H2 + O2 –> 2 H2O + heat energy

Question 22

what are 2 advantages and disadvantages for using hydrogen as a fuel

Answer 22

+ NO CO2 is produced
+ Renewable

– Explosive
– Hard to store

Question 23

what do we do to make a fair test for a calorimeter test

Answer 23

-heat same volume of water
-use same size copper can

Question 24

what material is the calorimeter made of, and why?

Answer 24

copper - it conducts heat better, transfers heat energy to water quickly

Question 25

why isn’t all of the heat energy that is released, transferred to the water

(in terms of calorimeter practical???)

Answer 25

the energy is lost to the surroundings at points throughout the experiment

Question 26

what is one way of improving the reliability of the calorimeter experiment

Answer 26

add an insulator to trap heat

Question 27

for ethanol to burn as a fuel, 3 things are required, what are they? and how can it be represented

Answer 27

-heat
-oxygen
-fuel

can be presented through the fire triangle

Question 28

what is the key to putting out a fire?

Answer 28

to remove one of the 3 components of a fire triangle

-oxygen
-heat
-fuel

Question 29

how would each component of the fire triangle be removed from a fire

Answer 29

-heat is removed with cold water

-oxygen is removed by fire blanket or CO2

-Fuel from fire is unlikely to be removed. but could cut down trees during a forest fire.

Question 30

what type of fire should water never be used to extinguish

Answer 30

electrical fire or oil fire

Question 31

what is cracking and what 2 things does it require

Answer 31

a reaction carried out to convert long chain hydrocarbons to short chain hydrocarbons.

-requires a high temperature
-requires a catalyst

Question 32

what are 2 advantages of cracking

Answer 32

-helps an oil refinery to convert long alkanes (which is low demand) to shorter alkanes (which is high demand)

-produces alkenes also, which can be used to make polymers (aka plastic)

Question 33

what are the two types of hydrocarbon

Answer 33

alkanes and alkenes

Question 34

how is the formula for an alkane set up

Answer 34

Cn+H2n + 2

eg. C5 + H12

2n so 5x2=10 and then plus 2 = 12

the numbers are meant to be small btw

Question 35

how many bonds can a carbon have, and how many can a hydrogen have?

Answer 35

a carbon can have 4 bonds to other atoms
hydrogen can only form 1 bond

Question 36

what is the name given to the molecules with the same molecular formula but different structural formula?

Answer 36

isomers

Question 37

how is the general formula for alkenes set up

Answer 37

C12+H24

numbers meant to be small

Question 38

what are the names of each carbon atom molecule thingy? (Alcohols)

Answer 38

meth - 1 carbon atom
eth - 2 carbon atoms
prop - 3 carbon atoms
but - 4 carbon atoms

(so its like propane for an alkane and propene for and alkene)

you need to remember these 4 names

Question 39

what are the 3 types of addition reactions

Answer 39

type 1 - hydrogenation- hydrogen
type 2 - bromination - bromine
type 3 - hydration - water

Question 40

Alkanes are saturated, what does this mean?

Answer 40

meaning that it contains the greatest possible number of atoms

and it has no double bonds because of this

Question 41

Alkenes are unsaturated, what does this mean?

Answer 41

meaning that it has a double bond between two carbon molecules, (like this C=C) meaning that it doesnt contain the greatest possible number of atoms

this double bond can be broken into a single bond (like this C-C) and when this happens, other atoms are able to bond to the other bond that just broke, which then means its now saturated.

Question 42

what do you observe from
bromine + alkane reaction
bromine + alkene reaction

Answer 42

bromine + alkane = no reaction because alkanes are saturated

bromine + alkene = turns from orange/brown to colorless

Question 43

what are polymers

Answer 43

long chain molecules made by adding together alkenes ( the alkenes are called monomers)

Question 44

what are 6 properties of polymers

Answer 44

flexible
strong
thermal and electrical insulators
resistant to corrosion
low density
dont rot

Question 45

what are 4 uses of polymers

Answer 45

polyethene - plastic bottles
polypropene - ropes
polyvinylchloride - drain pipes
polytetrafluoroethene - non-stick pans

Question 46

polymers are non biodegradable, so they cant be decomposed by bacteria and take centuries to rot

what are 4 issues with this

Answer 46

-landfill sites get filled quickly, wasting valuable land
-burning plastics makes toxic gases
-valuable plastics are wasted by dumping or burning
-time consuming to sort out different polymers, so recycling is difficult

Question 47

of the 3 alcohols, which one can form isomers?

Answer 47

propanol

propan-1ol and propan-2-ol

Question 48

how can ethanol be made

Answer 48

through fermentation

or

reacting ethene with water (steam)
ethane + water = ethanol

Question 49

why doesnt methene exist?

Answer 49

because for alkenes, each alkene has one double bond, and methene only has one carbon, it doesnt have another carbon to double bond with, so it doesn’t exist.