Module 4: Chemistry in Action

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Module 4Chemistry in Action
Mr Hawkridge
Marlborough School Science Faculty
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Chemistry in Action

• Crude oil
• Burning fuels
• Alkanes/Alkenes
• Cracking
• Polymers
• Plastics / Waste

• Uses of Enzymes
• Neutralization
• Furniture
• Uses of limestone
• Making limewater
• Revision

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Crude Oil
18 January, 2004
Marlborough School Science Faculty
AIMS

• To explain how crude oil is formed to look at
  its chemical structure

Mr Hawkridge
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Separation of Crude Oil

• Crude oil is separated by the process of
  fractional distillation
• Using fractional distillation a mixture of
  liquids can be separated using the fact that they
  boil at different temperatures

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Crude Oil

• Crude oil is actually a mixture of lots of
  different substances
• Bitumen (tar)
• Heavy Fuel Oil (ships)
• Lubricating Oil (any engine)
• Diesel (lorries)
• Kerosene (aeroplane fuel)
• Petrol (cars)
• Propane gas (camping gas)

• Task Make a PowerPoint holiday diary
• During your holiday you must use each chemical
  that is found in crude oil
• Include at least one slide about the structure of
  one of the substances
• Bonus marks will be added for an interesting
  presentation!

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Hydrocarbon Combustion
24 January, 2005
Marlborough School Science Faculty
AIMS

• To describe chemically what happens when fuels
  are burnt

Mr Hawkridge
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Chemicals in Crude Oil (H/W)

• Hydrocarbons contain Hydrogen and Carbon atoms
• One has 3 more carbons, it will have a slightly
  higher boiling point
• A. C5H12 B. C8H18 (2n 2 rule)
• Table
• The hydrocarbon with the biggest molecules boils
  at the highest temperature.

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Crude Oil Formation

• When sea creatures die they sink to the bottom of
  the sea and are covered in mud
• The heat and pressure change them into drops of
  oil
• 100s of million of years ago many creatures
  lived in the sea
• The oil travelled up and collected under a layer
  of rock with no cracks in it

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Hydrocarbon Combustion

• You Should Know
• When fuels burn, energy is released as thermal
  energy
• Oxidation is the addition of oxygen to a
  substance (so fuel is oxidised when burnt)
• Complete combustion (lots of oxygen)
• 2CH4 3O2 ? 2CO2 2H2O
• Incomplete combustion (limited oxygen)
• 2CH4 3O2 ? 2CO 4H2O

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Carbon Monoxide

• TASK
• Produce a pamphlet for a carbon monoxide
  detector. These look like a fire alarm but work
  on CO not smoke.
• REQUIREMENTS
• A picture and name for your CO detector
• Scientific Information If a fuel does not get
  enough oxygen when it burns carbon monoxide is
  made instead of carbon dioxide. This can happen
  if your gas cooker, boiler or fire is not well
  ventilated. Carbon monoxide gas has no smell and
  can kill.
• RESOURCES
• Page 133-4 Nelson Text (esp. Key Facts p.134)

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Cracking Up
25 January, 2005
Marlborough School Science Faculty
AIMS

• To learn how cracking some oil fractions produces
  other useful hydrocarbons

Mr Hawkridge
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Cracking Up

• You Should Know
• A catalytic cracker (right) breaks down large
  hydrocarbons into smaller ones
• This produces more petrol and uses up less
  desirable oil fractions
• Alkenes (CC) are also produced by cracking

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Homework

• Draw the stuctures of 3 possible products of the
  cracking of C16H34

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Cracking Up Cartoon

• TASK
• Create a cartoon strip to go with each of the
  following captions. Your cartoon must have at
  least 4 frames!
• They put the molecules into a machine which can
  heat them up.
• Scientists have too many long bitumen and fuel
  oil molecules. They cant sell them all.
• The scientists can then sell the short petrol
  molecules for lots of money!
• The long molecules are cracked (broken) into
  shorter petrol molecules. A catalyst speeds this
  up.

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Polymers 2
31 January, 2005
Marlborough School Science Faculty
AIMS

• To list some properties of different polymers

Mr Hawkridge
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Polymers Plastics

• You Should Know
• Plastics are made up of very long molecules
  called polymers
• These polymers are made from chains of smaller
  molecules called monomers
• Eg. Polystyrene (a polymer made of lots of
  styrene molecules)
• Polyethene (a polymer made of lots of ethene
  molecules)

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Polymers

• Plastics are made from very long molecules called
  polymers
• Polymers are made of lots of small molecules
  called monomers
• These monomers are linked together during a
  process called polymerisation

Monomers
Polymerisation
Polymer
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Polymerisation
Ethene
Ethene
Ethene
Ethene
Many ethene monomers join to make a long polymer
called POLYETHENE
Ethene
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Polymerisation
Styrene
Styrene
Styrene
Many styrene monomers join to make a long polymer
called POLYSTYRENE
Styrene
Styrene
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What Type of Molecules Can be Monomers?

• To be a monomer a molecule must have a double
  bond
• This can open up and allow the molecule to join
  to the next one
• Which of the molecules in the pictures can be
  monomers?

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Neutralization
7 February, 2005
Marlborough School Science Faculty
AIMS

• To understand that neutralization reactions
  produce a salt and water
• Neutralization is used to make fertilizer

Mr Hawkridge
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GCSE Coursework

• Accounts for 20 of your final mark
• Need at least 2 full pieces by Year 11
• You will be tested in 4 areas
• A good piece of coursework can greatly improve
  your grades at GCSE!

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Neutralization Planning (1-2 Pages)

• Use p.157-8 in Nelson or p. in Chem for U to find
  scientific background information about
  neutralization reactions
• Make a prediction
• Write a detailed method using numbered steps (use
  info from handout and Thursdays practise)
• Make sure you cover all the points on the
  Planning page in the GCSE Investigations booklet
  for maximum marks

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Neutralization Obtaining Evidence

• Perform the experiment carefully and record your
  results on a rough piece of paper
• Record results accurately (read Burettes
  correctly)
• Include proper units (cm3 etc.)
• Neatness is important here

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Thermal Decomposition
8 February, 2005
Marlborough School Science Faculty
AIMS

• To write an give examples of thermal
  decomposition reactions

Mr Hawkridge
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Neutralization Analysing (1-2 Pages)

• Present your results use words to describe, a
  graph, table or diagram
• Explain any mathematical calculations (average
  amount of acid)
• Write a conclusion based on your results. What do
  your results tell you?
• Explain your conclusion using SCIENCE details
  are important

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Neutralization Evaluating (1-2 Pages)

• Describe how effective the procedure was
• Comment on how accurate you think the experiment
  was, what affected the results?
• How accurate do you think your conclusion is?
• What specifically could be done to improve this
  experiment?