Specification Points Year 10 – Organic Chemistry Crude oil, hydrocarbons and alkanes - know • crude oil is a mixture of a large number of compounds, mainly hydrocarbons ( alkanes) • alkanes are a homologous series with a general formula of C n H 2n+2 • the names of the first four members of the alkanes Fractional distillation and petrochemicals - know • what a fraction is and how fractional distillation is used to separate fractions • that fractions are processed to produce fuels +feedstock for the petrochemical industry. • that fuels on which we depend for our modern lifestyle, such as petrol, diesel oil, kerosene, heavy fuel oil and liquefied petroleum gases, are produced from crude oil. • that many useful materials on which modern life depends are produced by the petrochemical industry, such as solvents, lubricants, polymers, detergents. Properties of hydrocarbons - know • how boiling point, flammability and viscosity of hydrocarbons is affected by the molecular size of a hydrocarbon molecule which affects its use as a fuel • and write equations for the complete combustion of a hydrocarbon fuel Cracking and alkenes - know • what cracking is, how it happens and why it is used • how to balance cracking equations and know the products of a cracking reaction • the test for alkenes • Cracking produces small molecules which have high demand for use in fuels and as a starting material for polymerisation Structure, formulae and reactions of alkenes - know • what an alkene is and the first 4 members of the homologous series • how to describe and write equations to show an alkene reacting with oxygen hydrogen, water and the halogens by the addition of atoms across the carbon-carbon double bond Polymers - know • what a polymer is, its bonding and how it is formed • know that the intermolecular forces between polymer molecules are relatively strong and so these substances are solids at room temperature. Addition polymerisation - know • that many small molecules (monomers) join to form large molecules (polymers). • how poly(ethene) and poly(propene) are made by addition polymerisation. • be able to recognise addition polymers and monomers from diagrams in the forms shown and from the presence of the functional group C=C in the monomers • be able to draw diagrams to show a polymer formed from a given alkene monomer in addition to identifying the monomer from polymers Ceramics, polymers and composites - know • how glass is made • how clay ceramics (pottery and bricks) are made. • how low density (LD) and high density (HD) poly(ethene) are produced from ethene Organic Chemistry
Transcript
Specification Points
Year 10 – Organic Chemistry
Crude oil, hydrocarbons and alkanes - know • crude oil is a mixture of a large number of compounds, mainly hydrocarbons ( alkanes) • alkanes are a homologous series with a general formula of CnH2n+2 • the names of the first four members of the alkanes
Fractional distillation and petrochemicals - know • what a fraction is and how fractional distillation is used to separate fractions • that fractions are processed to produce fuels +feedstock for the petrochemical industry. • that fuels on which we depend for our modern lifestyle, such as petrol, diesel oil,
kerosene, heavy fuel oil and liquefied petroleum gases, are produced from crude oil. • that many useful materials on which modern life depends are produced by the
petrochemical industry, such as solvents, lubricants, polymers, detergents.
Properties of hydrocarbons - know • how boiling point, flammability and viscosity of hydrocarbons is affected by the
molecular size of a hydrocarbon molecule which affects its use as a fuel • and write equations for the complete combustion of a hydrocarbon fuel
Cracking and alkenes - know • what cracking is, how it happens and why it is used • how to balance cracking equations and know the products of a cracking reaction • the test for alkenes • Cracking produces small molecules which have high demand for use in fuels and as a
starting material for polymerisation
Structure, formulae and reactions of alkenes - know • what an alkene is and the first 4 members of the homologous series • how to describe and write equations to show an alkene reacting with oxygen hydrogen,
water and the halogens by the addition of atoms across the carbon-carbon double bond
Polymers - know • what a polymer is, its bonding and how it is formed • know that the intermolecular forces between polymer molecules are relatively strong
and so these substances are solids at room temperature.
Addition polymerisation - know • that many small molecules (monomers) join to form large molecules (polymers). • how poly(ethene) and poly(propene) are made by addition polymerisation. • be able to recognise addition polymers and monomers from diagrams in the forms
shown and from the presence of the functional group C=C in the monomers • be able to draw diagrams to show a polymer formed from a given alkene monomer in
addition to identifying the monomer from polymers
Ceramics, polymers and composites - know • how glass is made • how clay ceramics (pottery and bricks) are made. • how low density (LD) and high density (HD) poly(ethene) are produced from ethene
Organic Chemistry
using different catalysts and reaction conditions. • what thermosoftening polymers and thermosetting polymers are and relate their
properties to their structures • what a composite is and be able to give examples • be able to compare quantitatively the physical properties of glass and clay ceramics,
polymers, composites and metals • be able to explain how the properties of materials relate to their uses
Year 11 Organic Chemistry
Alcohols Alcohols contain the functional group –OH. Methanol, ethanol, propanol and butanol are the first four members of a homologous series of alcohols. Alcohols can be represented in the following forms: CH3CH2OH or structural formulae Methanol, ethanol, propanol and butanol: • dissolve in water to form a neutral solution • react with sodium to produce hydrogen • burn in air to produce carbon dioxide and water • are oxidised to produce carboxylic acids • are used as fuels and solvents, and ethanol is the main alcohol in alcoholic drinks. Aqueous solutions of ethanol are produced when sugar solutions are fermented using yeast. Be able to: • recognise alcohols from their names or from given formulae up to butanol • know the conditions used for fermentation of sugar using yeast. • write balanced chemical equations for the reactions of alcohols other than for
combustion reactions.
Carboxylic acids Carboxylic acids have the functional group – COOH. The first four members of a homologous series of carboxylic acids are methanoic acid, ethanoic acid, propanoic acid and butanoic acid. Carboxylic acids: • dissolve in water to produce acidic solutions • react with carbonates to produce carbon dioxide • do not ionise completely when dissolved in water and so are weak acids • react with alcohols in the presence of an acid catalyst to produce esters, for example
ethanoic acid reacts with ethanol to produce ethyl ethanoate and water. Be able to • recognise carboxylic acids from their names or from given formulae up to butanoic acid. • write balanced chemical equations for the reactions of carboxylic acids. • know the name of esters ethyl ethanoate.
Condensation polymerisation • Condensation polymerisation involves monomers with two functional groups. When
these types of monomers react they join together, usually losing small molecules such as water, and so the reactions are called condensation reactions.
• The simplest polymers are produced from two different monomers with two of the same functional groups on each monomer. For example: ethane diol and hexanedioic acid polymerise to produce a polyester:
• Be able to explain the principles of condensation polymerisation in relation to the functional groups in the monomers and the repeating units in the polymers.
Amino acids • Amino acids have two different functional groups in a molecule. Amino acids react by
condensation polymerisation to produce polypeptides. • For example: glycine is H2NCH2COOH and polymerises to produce the polypeptide
(-NCH2COO-)n and nH2O. • Different amino acids can be combined in the same chain to produce proteins.
DNA (deoxyribonucleic acid) and other naturally occurring polymers • DNA (deoxyribonucleic acid) is a large molecule essential for life. DNA encodes genetic
instructions for the development and functioning of living organisms and viruses. • Most DNA molecules are two polymer chains, made from four different monomers
called nucleotides, in the form of a double helix. Other naturally occurring polymers important for life include proteins, starch and cellulose. Proteins are polymers of amino acids. Starch and cellulose are polymers of sugars. Sugars, starch and cellulose are carbohydrates.
Independent Study suggestions
1. Look at the specification points above – use the textbook pages (244-277) to make a few notes/spider diagram/revision cards
2. Watch the Fuse School short 3-4 minute explanation videos on any area you need extra help with:
Coal, oil and gas: https://www.fuseschool.org/topics/59/contents/828
Carbohydrates: https://www.fuseschool.org/topics/59/contents/884 3. Now have a go at the past paper questions below which you can then mark using the markscheme at
Energy released = ...................................... kJ (2)
(ii) Suggest one improvement to the apparatus, or the use of the apparatus, that would make the temperature increase of the water for each fuel more accurate.
Mean time = ................................... seconds (1)
(iii) Complete the sentence.
As the number of carbon atoms in a molecule of liquid hydrocarbon increases, the time taken for the liquid hydrocarbon to run out of the funnel ................................................ .
(1)
(iv) A ring has been drawn around one result in Table 1.
This result has not been used to calculate the mean time for C10H22 Suggest why this result was not used.
(v) The apparatus the student used in Figure 2 could lead to a systematic error in the results. Identify one source of systematic error, and describe how the student could avoid or reduce the error.
(d) Ethene molecules form the polymer poly(ethene). One molecule in poly(ethene) will contain thousands of carbon atoms. The diagram represents part of a poly(ethene) molecule.
Propene molecules form the polymer poly(propene).
Draw a diagram to represent part of a poly(propene) molecule.
(2)
(Total 9 marks)
Q6.Ethene is used to produce poly(ethene).
(a) Draw the bonds to complete the displayed formulae of ethene and poly(ethene) in the equation.
(2)
(b) Polyesters are made by a different method of polymerisation.
The equation for the reaction to produce a polyester can be represented as:
Compare the polymerisation reaction used to produce poly(ethene) with the polymerisation reaction used to produce a polyester.
allow named catalyst eg zeolite, Al2O3, silica, ceramic
allow in the absence of air / oxygen 1
ignore any references to pressure
(ii) colourless
allow decolourised
ignore clear / discoloured 1
(iii) 1
(b) (i) 20.3(0) (kJ)
if answer incorrect allow 1 mark for 24.36/1.2 2
(ii) use a lid
allow insulate beaker or use draught shield 1
reduce energy / heat loss
ignore references to thermometer or repeats or distance of flame or loss of water
vapour
allow stir (1) to distribute energy / heat (1)
allow use a metal can (1) as it’s a better conductor (1) 1
(iii) carbon/soot
ignore tar, smoke 1
(produced by) incomplete combustion
allow from a limited supply of oxygen/air 1
(iv) hexane gives out the greatest energy (per 1.0 g)
ignore more energy 1
hexane produces the least smoke / carbon / soot
allow has the cleanest flame
ignore less smoke / carbon / soot 1
(c) Marks awarded for this answer will be determined by the Quality of Written Communication (QWC) as well as the standard of the scientific response. Examiners should also apply a ‘best-fit’ approach to the marking.
Level 3 (5 – 6 marks): Descriptions of advantages and disadvantages that are linked to their own knowledge.
Level 2 (3 – 4 marks): Descriptions of an advantage and a disadvantage with some use of their knowledge to add value.
Level 1 (1 – 2 marks): Statements made from the information that indicate whether at least one statement is an advantage or a disadvantage or a linked advantage or disadvantage
0 marks: No relevant content
Examples of the added value statements and links made in the response could include: Note that link words are in bold; links can be either way round. Accept reverse arguments and ignore cost throughout.
Advantages of using hydrogen: • Combustion only produces water so causes no pollution • Combustion does not produce carbon dioxide so this does not contribute to global warming or climate change • Combustion does not produce sulfur dioxide so this does not contribute to acid rain • Incomplete combustion of petrol produces carbon monoxide that is toxic • Incomplete combustion of petrol produces particulates that contribute to global dimming • Petrol comes from a non-renewable resource but there are renewable/other methods
of producing hydrogen • Hydrogen releases more energy so less fuel needed or more efficient
Disadvantages of using hydrogen: • Hydrogen is a gas so is difficult to store or transfer to vehicles • Hydrogen gas is very flammable so leaks cause a greater risk of explosion • Most hydrogen is produced from fossil fuels which are running out • Cannot be used in existing car engines so modification / development or replacement is needed • Lack of filling stations so difficult to refuel your vehicle
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[18]
M3.(a) (i) (conical) flask 1
(ii) measuring cylinder / pipette / burette 1
(b) (i) any two from: • so anomalous results could be identified / ignored • so a mean / average could be taken • (to improve) accuracy
2
(ii) 19 1
(iii) increases / gets longer / gets bigger 1
(iv) anomalous / does not agree with other times for C10H22
1
(v) any one from: • shorter hydrocarbon used • volume of hydrocarbon too small • started timing late • stopped timing too early / when liquid left in funnel
must suggest why the result is lower than the others.
allow the temperature was higher or the students used a wider funnel. 1
(c) (i) flammable 1
(ii) suitable safety precaution 1
reason that links the safety precaution to the hazard symbols
eg:
• wear gloves
• (because) it is hazardous to health / harmful / toxic / irritant
or
• do not pour down sink or dispose of properly
• (because) it is harmful to the environment / kills fish
or
• wear a mask or do it in the fume cupboard or a well-ventilated area
• respiratory irritant 1
(d) (i) points plotted correctly (within half small square)
all six points correct scores 2
3, 4 or 5 points correct scores 1 2
smooth curve of best fit 1
(ii) point at 46 °C circled
allow point furthest from the line as drawn 1
(iii) working shown on graph 1
value read from graph line drawn (within half small square) 1
(iv) the higher the temperature the lower the viscosity
allow the higher the temperature the lower / shorter the time taken for 1 mark 2
non-linear or change gets smaller as temperature gets higher
answer relating temperature to time taken can score a maximum of 2 marks. 1
(v) identifying source of the error 1
method of avoiding the error
eg:
• the temperature will drop
• insulate the funnel
or
• runs out before all added
• put a tap on the funnel 1
[22]
M4. (a) (i) heat / evaporate the crude oil / change to gas or vapour
do not accept heat with catalyst 1
cool / condense (hydrocarbons)
allow small molecules at top and / or large molecules at bottom 1
at different temperatures / boiling points
if the answer describes cracking ‘ no marks 1
(ii) C4H10
1
(b) H H H │ │ │ H ─C ─ C ─ C ─ H │ │ │ H H H
1
(c) (i) C5 to C8 fraction are fuels or easier to burn or petrol (fraction)
accept C21 to C24 fraction not useful as fuels
do not accept produce more energy 1
(ii) C2H4
do not accept C4H8
1
(iii) any three from:
• use different / lighter crude oils
• develop markets for low demand fractions
• develop new techniques / equipment to use low demand fractions as fuels
• cracking
• convert low demand fractions to high demand fractions or bigger molecules to smaller molecules
• develop alternative / bio fuels
do not accept price 3
[10]
M5. (a) vaporise / evaporate
allow boil for vaporise 1
different condensing points / temperatures
accept condense at different levels
ignore different size molecules or different densities
mention of cracking = max 1
allow boils at different temperatures and condenses for 2 marks
if no other marks awarded allow
fractional distillation for 1 mark 1
(b) (i) 3 (C2H4)
accept +C4H8
1
(ii) (decane / naphtha / hydrocarbon) vaporise / evaporate
allow crude oil
allow boil for vaporise 1
(passed over) a catalyst / alumina / porous pot
ignore other names of catalysts 1
(c) any two from:
‘they’ must be clarified
• alkanes / butane (molecules) do not have a (carbon carbon) double bond / are saturated / have (carbon carbon) single bonds
• alkenes / ethene (molecules) have (carbon carbon) double bonds
or are unsaturated
• alkenes / ethene molecules are able to bond to other molecules 2
(d) single bonds between carbon atoms
– C - C – 1
the -CH3 group appears on each pair of carbons on the ‘chain’
NB any double bonds = 0 marks 1
[9]
M6.(a) (ethene)
1
(polyethene)
1
(b) any four from:
• poly(ethene) produced by addition polymerisation whereas polyester by condensation polymerisation
• poly(ethene) produced from one monomer wheareas polyester produced from two different monomers
• poly(ethene) produced from ethene / alkene whereas polyester from a (di)carboxylic acid and a diol / alcohol
• poly(ethene) is the only product formed whereas polyester water also produced
• poly(ethene) repeating unit is a hydrocarbon whereas polyester has an ester linkage
4
[6]
M7.(a) fermentation 1
(b) (i) turns cloudy / milky / white
ignore bubbles 1
because carbon dioxide is produced
allow CO2 produced 1
(ii) filter paper 1
[4]
M8.(a) any two from:
• fuel
allow source of energy • solvent
allow perfume / aftershave • antiseptic
allow antibacterial 2
(b) Hydrogen 1
(c) (i) oxidation
do not allow redox 1
(ii) correct structure 1
(iii) ethanoic acid is a weak / weaker acid
it = ethanoic acid 1
because it does not completely ionise.
allow because it does not completely dissociate
allow it has a lower concentration of hydrogen ions
