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TRANSCRIPT
C8 Chemical Analysis35 Questions
Name: ________________________
Class: ________________________
Date: ________________________
Time:
Marks:
Comments:
Page 1 of 92Brookvale Groby Learning Trust
The apparatus in the figure below is used to separate a mixture of liquids in a fuel.
(a) What is apparatus W on above the figure above?
Tick one box.
Beaker
Boiling Tube
Flask
Jug
(1)
1
Page 2 of 92Brookvale Groby Learning Trust
(b) What is the name of this method of separation?
Tick one box.
Crystallisation
Electrolysis
Filtration
Distillation
(1)
(c) Name the changes of state taking place at A and B in the figure above.
Use words from the box.
boiling condensing freezing melting
Change of state at A: _________________________________________________
Change of state at B: _________________________________________________
(2)
Page 3 of 92Brookvale Groby Learning Trust
(d) Table 1 shows the boiling points of the hydrocarbons in the fuel.
Table 1
HydrocarbonBoiling point
in °C
Pentane 36
Hexane 69
Heptane 98
Octane 125
Which hydrocarbon will be the last to collect in the beaker?
Tick one box.
Pentane
Hexane
Heptane
Octane
(1)
Page 4 of 92Brookvale Groby Learning Trust
(e) The fuel is a mixture of liquids that has been designed as a useful product.
What name is given to this type of mixture?
Tick one box.
Catalyst
Formulation
Polymer
Solvent
(1)
(f) Describe how this fuel is different from crude oil.
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(2)
Page 5 of 92Brookvale Groby Learning Trust
(g) A student measured the melting point of a solid hydrocarbon four times.
The student’s results are in Table 2.
Table 2
Trial 1 Trial 2 Trial 3 Trial 4
Melting pointin °C
35 48 37 37
Calculate the mean melting point of the hydrocarbon, leaving out any anomalous result.
Give your answer to two significant figures.
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Mean melting point = __________________ °C
(2)
(Total 10 marks)
Page 6 of 92Brookvale Groby Learning Trust
A student used paper chromatography to investigate the colours in different inks.
Figure 1 shows the apparatus the student used.
Figure 1
(a) The student made two mistakes in setting up the apparatus.
Identify the two mistakes.
Describe the problem each mistake would cause.
Mistake 1 __________________________________________________________
Problem __________________________________________________________
___________________________________________________________________
___________________________________________________________________
Mistake 2 __________________________________________________________
Problem __________________________________________________________
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(4)
2
Page 7 of 92Brookvale Groby Learning Trust
(b) The student then set up the apparatus without making any mistakes.
Figure 2 shows his results.
Figure 2
What colours are in the black ink?
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(1)
(c) Which of the inks is the most soluble in the solvent?
Give a reason for your answer.
Ink _____________________________________________________________
Reason ___________________________________________________________
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(2)
Page 8 of 92Brookvale Groby Learning Trust
(d) Use Figure 2 to complete the table below, then calculate the Rf value for red ink.
Distance in mm
Distance moved by red ink ________________________
Distance from start line to solvent front ________________________
The Rf value for red ink is calculated using the equation.
Rf =
Give your answer to two significant figures.
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Rf value = _____________________________
(5)
(e) How can you tell from Figure 2 that the Rf value for the blue ink is greater than the Rf valuefor the red ink?
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(1)
(Total 13 marks)
Page 9 of 92Brookvale Groby Learning Trust
Rainwater is collected from the roofs of houses as shown in Figure 1.
Figure 1
(a) The water in the storage tank is not potable.
What does potable mean?
Tick one box.
Contains dissolved substances
Pure
Safe to drink
Tastes nice
(1)
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Page 10 of 92Brookvale Groby Learning Trust
(b) Why should the water in the tank be filtered to make it potable?
Tick one box.
To kill microbes
To remove dissolved gases
To remove dissolved solids
To remove undissolved solids
(1)
(c) A gas which bleaches litmus paper can be added to the water to make it potable.
Name this gas and explain why it is added.
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(2)
Page 11 of 92Brookvale Groby Learning Trust
(d) The storage tank is made from concrete reinforced with steel wire, as shown in Figure 2.
Figure 2.
Figure 3 shows how the distance between the steel wires affects the relative strength ofthe concrete.
Figure 3
Use values from Figure 3 to describe the relationship shown by the graph.
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(2)
(Total 6 marks)
Page 12 of 92Brookvale Groby Learning Trust
Aqamed is a medicine for children.
(a) The medicine is a formulation.
What is meant by a formulation?
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(1)
4
(b) Children often do not like taking medicine.
Suggest a substance that could be added to Aqamed to increase the desire for children totake it.
Give a reason for your suggestion.
Substance _________________________________________________________
Reason ____________________________________________________________
___________________________________________________________________
(2)
(c) The main ingredient in Aqamed is a painkiller called paracetamol.
The figure below represents a molecule of paracetamol.
Give the molecular formula of paracetamol.
Calculate its relative formula mass (Mr).
Relative atomic masses (Ar): H = 1; C = 12; N = 14; O = 16
Molecular formula ____________________________________________________
Relative formula mass ________________________________________________
___________________________________________________________________
Mr = _____________________________
(2)
Page 13 of 92Brookvale Groby Learning Trust
(d) Aspirin is a medicine for use by adults.
An aspirin tablet contains 300 mg of acetylsalicylic acid.
Calculate the number of moles of acetylsalicylic acid in one aspirin tablet.
Give your answer in standard form to three significant figures.
Relative formula mass (Mr) of aspirin = 180
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Number of moles = ______________________
(4)
(Total 9 marks)
Page 14 of 92Brookvale Groby Learning Trust
The figure below shows a paper chromatogram of five different inks.
(a) Explain how paper chromatography separates substances.
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(3)
5
(b) Analyse the chromatogram. Describe and explain the result for black ink.
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(4)
Page 15 of 92Brookvale Groby Learning Trust
(c) Use the figure above to calculate the Rf value of the blue ink.
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Rf value = ___________________________
(3)
(Total 10 marks)
Page 16 of 92Brookvale Groby Learning Trust
Chromatography can be used to separate components of a mixture.
(a) A student used paper chromatography to analyse a black food colouring.
The student placed spots of known food colours, A, B, C, D and E, and the black foodcolouring on a sheet of chromatography paper.
The student set up the apparatus as shown in Diagram 1.
Diagram 1
The student made two errors in setting up the apparatus.Identify the two errors and describe the problem each error would cause.
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(4)
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Page 17 of 92Brookvale Groby Learning Trust
(b) A different student set up the apparatus without making any errors.
The chromatogram in Diagram 2 shows the student’s results.
Diagram 2
(i) What do the results tell you about the composition of the black food colouring?
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______________________________________________________________
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(2)
(ii) Use Diagram 2 to complete Table 1.
Table 1
Distance in mm
Distance from start line to solvent front ______________
Distance moved by food colour C ______________
(2)
(iii) Use your answers in part (b) (ii) to calculate the Rf value for food colour C.
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______________________________________________________________
Rf value = ____________________
(1)
Page 18 of 92Brookvale Groby Learning Trust
(c) Table 2 gives the results of chromatography experiments that were carried out on someknown food colours, using the same solvent as the students.
Table 2
Name of foodcolour
Distance from startline to solvent front
in mm
Distance moved byfood colour in mm
Rf value
Ponceau 4R 62 59 0.95
Carmoisine 74 45 0.61
Fast red 67 27 0.40
Erythrosine 58 17 0.29
Which of the food colours in Table 2 could be food colour C from the chromatogram?
Give the reason for your answer.
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(2)
(d) Two types of chromatography are gas chromatography and paper chromatography.
Give one advantage of gas chromatography compared with paper chromatography.
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(1)
(Total 12 marks)
Page 19 of 92Brookvale Groby Learning Trust
A student was trying to produce hydrogen gas.
Figure 1 shows the apparatus she used.
Figure 1
(a) No gas was produced.
The student’s teacher said that this was because the substances in the flask did not react.
(i) Suggest why the substances in the flask did not react.
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(1)
7
(ii) Which two substances could the student have put in the flask to produce hydrogensafely?
Tick (✓) one box.
Gold and dilute hydrochloric acid
Potassium and dilute hydrochloric acid
Zinc and dilute hydrochloric acid
(1)
Page 20 of 92Brookvale Groby Learning Trust
(b) Another student did produce hydrogen from two substances.
Figure 2 shows the apparatus the student used to collect and measure the volume of thehydrogen gas.
Figure 2
Give the name of the apparatus labelled X.
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(1)
(c) The student did the experiment four times. Her results are shown in the table below.
Experiment Volume of hydrogen collected inone minute in cm3
1 49
2 50
3 35
4 48
(i) One of the results is anomalous.
Which result is anomalous? Write your answer in the box.
Give a reason for your choice.
______________________________________________________________
(2)
Page 21 of 92Brookvale Groby Learning Trust
(ii) Calculate the mean volume of hydrogen collected in one minute.
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Mean volume = ____________________ cm3
(2)
(iii) Give a reason why the experiment should be repeated several times.
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(1)
(d) A teacher collected two tubes full of hydrogen gas, as shown in Figure 3.
Figure 3
She tested tube A with a lighted splint as soon as she took the bung out.
She tested tube B with a lighted splint a few seconds after taking the bung out.
(i) Suggest why tube B gave a much louder pop than tube A.
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(1)
Page 22 of 92Brookvale Groby Learning Trust
(ii) Complete and balance the chemical equation for the reaction that takes place whenthe hydrogen reacts in this test.
H2 + O2
(2)
(Total 11 marks)
The label shows the ingredients in a drink called Cola.
Cola
Ingredients:
Carbonated waterSugarColouringPhosphoric acidFlavouringCaffeine
(a) (i) The pH of carbonated water is 4.5.
The pH of Cola is 2.9.
Name the ingredient on the label that lowers the pH of Cola to 2.9.
______________________________________________________________
(1)
8
(ii) Which ion causes the pH to be 2.9?
______________________________________________________________
(1)
Page 23 of 92Brookvale Groby Learning Trust
(b) A student investigated the food colouring in Cola and in a fruit drink using paperchromatography.
The chromatogram in the figure below shows the student’s results.
Cola Fruit drink
(i) Complete the sentence.
The start line should be drawn with a ruler and ___________________ .
Give a reason for your answer.
______________________________________________________________
______________________________________________________________
(2)
(ii) Suggest three conclusions you can make from the student’s results.
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(3)
(c) Caffeine can be separated from the other compounds in the drink by gas chromatography.
Why do different compounds separate in a gas chromatography column?
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(1)
Page 24 of 92Brookvale Groby Learning Trust
(d) Caffeine is a stimulant.
Large amounts of caffeine can be harmful.
(i) Only one of the questions in the table can be answered by science alone.
Tick ( ) one question.
Question Tick ( )
Should caffeine be an ingredient in drinks?
Is there caffeine in a certain brand ofdrink?
How much caffeine should people drink?
(1)
(ii) Give two reasons why the other questions cannot be answered by science alone.
Reason 1 ______________________________________________________
______________________________________________________________
Reason 2 ______________________________________________________
______________________________________________________________
(2)
(Total 11 marks)
Page 25 of 92Brookvale Groby Learning Trust
Carbon dioxide is produced when copper carbonate is heated.
A student investigated heating copper carbonate.The student used the apparatus to measure how long it took for carbon dioxide to beproduced.The student also noted what happened during each minute for three minutes.
(a) The student used changes to the limewater to measure how long it took for carbon dioxideto be produced.
Describe how.
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(2)
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Page 26 of 92Brookvale Groby Learning Trust
(b) The student wrote down her observations.
Time intervalin minutes
Observations
Between 0 and 1A slow release of gas bubbles.The limewater did not change.The solid in the test tube was green.
Between 1 and 2A fast release of gas bubbles.The limewater changed at 1 minute 10 seconds.
Between 2 and 3No release of gas bubbles.The solid in the test tube was black.
(i) Suggest the reason for the student’s observations between 0 and 1 minute.
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(2)
(ii) Explain the student’s observations between 1 and 2 minutes.
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(2)
(iii) Explain the student’s observations between 2 and 3 minutes.
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(2)
Page 27 of 92Brookvale Groby Learning Trust
Colours are used to coat some chocolate sweets.
Some of these colours are given E-numbers.
Use the correct word from the box to complete the sentence.
additive element fuel
An E-number is used to identify a permitted food ____________________________
(1)
10
(b) Chromatography was used to compare three of the colours used to coat the chocolatesweets.
What do these results tell you about these three colours?
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(3)
(Total 4 marks)
Page 28 of 92Brookvale Groby Learning Trust
This is part of an article about food additives.
THE PERIL OF FOOD ADDITIVES
Some orange drinks contain the additives E102 (Tartrazine),E104 (Quinoline Yellow) and E110 (Sunset Yellow).Thesethree coloured additives are thought to cause hyperactivity inchildren.
(a) State two reasons that a manufacturer might give to justify the use of these additives.
1. _________________________________________________________________
___________________________________________________________________
2. _________________________________________________________________
___________________________________________________________________
(2)
11
(b) Some scientists asked 4000 twelve-year-old children to help them investigate if there is alink between these three coloured additives and hyperactivity.
How would the scientists use these 4000 children to investigate if there is a link betweenthese three coloured additives and hyperactivity in children?
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(4)
(c) A manufacturer used an independent scientist to show that their orange drink did notcontain these three coloured additives.
(i) Suggest why the manufacturer would use a scientist who was independent instead ofusing their own scientist.
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(1)
Page 29 of 92Brookvale Groby Learning Trust
(ii) The scientist had samples of E102, E104 and E110 and the orange drink. Thescientist used paper chromatography for the test.
Describe how the scientist could use the results to show if the orange drink containedany of these three coloured additives.
You may include a diagram of the paper chromatography results.
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(2)
(Total 9 marks)
A student was investigating the reaction of lithium and water.
She added a few drops of universal indicator to water in a trough and added a piece of lithium.
The word equation for the reaction is:
lithium + water lithium hydroxide + hydrogen
(a) (i) The lithium floated on the water.
State two other observations that the student would see during the reaction.
1. ____________________________________________________________
2. ____________________________________________________________
(2)
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Page 30 of 92Brookvale Groby Learning Trust
(ii) Balance the symbol equation for the reaction of lithium and water.
2 Li(s) + _____ H2O(l) _____ LiOH(aq) + H2(g)
(2)
(iii) Describe a simple test and the result that would show the gas was hydrogen.
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(1)
(iv) All Group 1 metals have similar reactions with water.
State why, in terms of electronic structure.
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(1)
(b) Lithium and other Group 1 metals have different properties from the transition metals.
Tick (✔) two properties that are properties of Group 1 metals.
They react with oxygen.
They form coloured compounds.
They are strong and hard.
They have low melting points.
(2)
Page 31 of 92Brookvale Groby Learning Trust
(c) The electronic structure of a potassium atom is 2, 8, 8, 1
(i) Draw a diagram to show the electronic structure of a potassium ion.
Show the charge on the potassium ion.
(2)
(ii) Potassium is more reactive than sodium.
Explain why, in terms of electronic structure.
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(3)
(Total 13 marks)
Carbon dioxide is produced when metal carbonates are heated.
(a) (i) Draw a ring around the correct answer to complete the word equation.
(1)
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Page 32 of 92Brookvale Groby Learning Trust
(ii) Draw a ring around the correct answer to complete the sentence.
combustion.
The reaction to produce carbon dioxide from magnesium carbonate is decomposition.
fermentation.
(1)
Page 33 of 92Brookvale Groby Learning Trust
(b) A student investigated what happens when metal carbonates are heated.
The student:
• used the apparatus to investigate heating four metal carbonates
• started the stop clock at the same time as he began to heat the metal carbonate
• stopped the stop clock when carbon dioxide was produced.
The student’s results are shown in the table.
Metal carbonateTime taken for the production of carbon
dioxide to start in seconds
Calcium carbonate 163
Copper carbonate 24
Magnesium carbonate 92
Zinc carbonate 67
(i) Tick ( ) the type of graph the student should draw from these results.
Type of graph Tick ( )
Bar chart
Line graph
Scatter graph
(1)
Page 34 of 92Brookvale Groby Learning Trust
(ii) Use the Chemistry Data Sheet to help you to answer this question.
Draw a ring around the correct answer to complete the sentence.
less
The more reactive the metal in the carbonate the more time is
same
taken for the production of carbon dioxide to start.
(1)
(iii) How did the student know that carbon dioxide was produced?
Use the diagram of the apparatus to help you to answer this question.
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(2)
(Total 6 marks)
Limestone is used as a building material. Acid rain erodes limestone.
(a) Limestone contains calcium carbonate.The symbol equation for the reaction of calcium carbonate with hydrochloric acid is shown.
CaCO3(s) + 2HCl(aq) → CaCl2(aq) + H2O(l) + CO2(g)
Describe a test to show that carbon dioxide is produced in this reaction.
Give the result of the test.
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(2)
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Page 35 of 92Brookvale Groby Learning Trust
(b) Gases from vehicle exhausts produce sulfuric acid and nitric acid.
A student investigated the reaction of these two acids with calcium carbonate (limestone).The type of acid was changed but all other variables were kept the same.The student measured the volume of carbon dioxide produced each minute for a total of 10minutes. He did this first for the reaction between dilute sulfuric acid and a cube of calciumcarbonate (limestone).The student repeated the experiment using dilute nitric acid in place of the dilute sulfuricacid.The results are shown below.
(i) State two variables that must be kept the same for this investigation.
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(2)
Page 36 of 92Brookvale Groby Learning Trust
(i) Reacting calcium carbonate with sulfuric acid gave different results to nitric acid.
The symbol equations for the reaction of calcium carbonate with sulfuric acid andwith nitric acid are shown below.
CaCO3(s) + H2SO4(aq) → CaSO4(s) + H2O(l) + CO2(g)
CaCO3(s) + 2HNO3(aq) → Ca(NO3)2(aq) + H2O(l) + CO2(g)
Describe how the results for sulfuric acid are different and use the symbol equationsto explain this difference.
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(3)
(Total 7 marks)
Page 37 of 92Brookvale Groby Learning Trust
An article began:
Ban yellow additives
Quinoline yellow (E104) is suspected of causing hyperactivity, asthma and rashes inchildren.
(a) A student tested a food to find out if it contained quinoline yellow (E104).The student’s results are shown below.
(i) Draw a ring around the correct answer to complete the sentence.
chromatography.
This method of detecting and identifying colours is called distillation.
electrolysis.
(1)
15
(ii) Using the student’s results, how many different colours are in the food? ___
(1)
(iii) Using the student’s results, how can you tell that the food does not contain quinolineyellow (E104)?
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(1)
Page 38 of 92Brookvale Groby Learning Trust
(b) Quinoline yellow (E104) is used in foods such as sweets, drinks and ice cream.
(i) Give one reason why quinoline yellow (E104) is added to foods.
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(1)
(ii) Suggest what should be done to decide if quinoline yellow (E104) should be banned.
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(1)
(Total 5 marks)
Page 39 of 92Brookvale Groby Learning Trust
Human stomachs contain hydrochloric acid.Stomach ache can be caused by too much acid in the stomach.Indigestion tablets can be used to reduce the amount of acid in the stomach.
(a) The graph shows how the volume of carbon dioxide produced changes with time, aftersome calcium carbonate is added to hydrochloric acid.
(i) Complete the sentence to explain what happens between Oand P.
Between O and P the calcium carbonate and hydrochloric acid _________
(1)
16
(ii) Complete the sentence to explain what happens at P.
At P the calcium carbonate and hydrochloric acid __________________
because __________________________________________________
(2)
Page 40 of 92Brookvale Groby Learning Trust
(iii) Describe the test for carbon dioxide gas.
Test ____________________________________________________
Result of the test __________________________________________
(2)
(b) Calcium carbonate is found in limestone.Limestone is removed from the ground by quarrying.
Photograph supplied by Stockbyte/Thinkstock
Tick ( ) oneadvantage and tick ( ) onedisadvantage of quarrying limestone.
StatementAdvantage
Tick ( )Disadvantage
Tick ( )
Quarrying limestone destroys the shells and skeletons ofmarine organisms that formed the limestone.
Quarrying limestone releases dust, and lorries releasecarbon dioxide from burning diesel fuel.
Quarrying limestone provides building materials,employment and new road links.
Quarrying limestone removes ores from the ground.
(2)
(Total 7 marks)
Page 41 of 92Brookvale Groby Learning Trust
Icing on cakes is tested to check that safe colours were used when they were made.
By Megan Chromik [CC-BY-SA-2.0], via Wikimedia Commons
Paper chromatography is one method of testing which colours are in cake icing.
17
(a) The diagram shows an experiment a student did.
(i) Suggest why there is a lid on the container.
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(1)
Page 42 of 92Brookvale Groby Learning Trust
(ii) The start line should be drawn in pencil not in ink.Suggest why.
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(1)
(b) The diagram shows the results of the paper chromatography experiment.
(i) How many different food colours were used in the colouring from the cake icing?
______________________
(1)
(ii) Is the cake icing safe to eat?
Give a reason for your answer.
______________________________________________________________
______________________________________________________________
(1)
(c) Gas chromatography linked to mass spectroscopy is an example of an instrumentalmethod. This method was used on a mixture of solvents.
(i) Give two advantages of gas chromatography compared with paper chromatography.
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(2)
Page 43 of 92Brookvale Groby Learning Trust
(ii) What does gas chromatography do to the mixture of solvents?
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(1)
(iii) What information does mass spectroscopy give?
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(1)
(Total 8 marks)
Page 44 of 92Brookvale Groby Learning Trust
Read the article.
Problem food colourings
Scientists say they have evidence that somefood colourings cause hyperactive behaviour inyoung children.
These food colourings are added to some sweets.
W, X, Y and Z are food colourings that may cause hyperactive behaviour in young children.
A scientist used chromatography to see if these food colourings were used in two sweets, S andP.
The results are shown on the chromatogram.
(a) Food colourings, such as W, X, Y and Z, are added to some sweets.
Suggest one reason why.
___________________________________________________________________
___________________________________________________________________
(1)
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Page 45 of 92Brookvale Groby Learning Trust
(b) In chromatography, the Rf value =
Use the scale on the chromatogram to help you to answer this question.
Which food colouring, W, X, Y or Z, has an Rf value of 0.7?
(1)
(c) From the chromatogram, what conclusions can the scientist make about the colourings insweets S and P?
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(3)
(Total 5 marks)
Page 46 of 92Brookvale Groby Learning Trust
This is part of an article about food additives.
THE PERIL OF FOOD ADDITIVES
Some orange drinks contain the additives E102 (Tartrazine),E104 (Quinoline Yellow) and E110 (Sunset Yellow).These three additives are thought to cause hyperactivity in children.
(a) Tick ( ) two reasons why a manufacturer of orange drinks uses these additives.
Reason Tick ( )
to make the drink healthier
to improve the appearance of the drink
because they are permitted colours
because they are expensive
(2)
19
(b) A scientist tested an orange drink to find out if it contained these additives.The result of the test is shown.
(i) Draw a ring around the correct answer to complete the sentence.
chromatography.
The test that the scientist did is called cracking.
distillation.
(1)
Page 47 of 92Brookvale Groby Learning Trust
(ii) How many coloured additives are there in the orange drink? _____________
(1)
(iii) The scientist concluded that the orange drink contained only one of the additivesE102, E104 and E110.
Explain why.
______________________________________________________________
______________________________________________________________
______________________________________________________________
______________________________________________________________
(2)
(Total 6 marks)
The result of a process used to detect and identify the colours in two foods, A and B, is shown.
20
(i) Describe the differences between the colours used in food A and food B.
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___________________________________________________________________
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(2)
Page 48 of 92Brookvale Groby Learning Trust
(ii) Tick ( ) the name of the process used to detect and identify colours in food.
Process ( )
chromatography
extraction
hardening
(1)
(Total 3 marks)
Chromatography was carried out on a sample of soft drinks to check that they contained onlycolours that were safe. This is the result.
Safe colours Colours from the soft drinks
What conclusions about the safety of the colours in the soft drinks A, B, C and D can be madefrom the results shown by chromatography?
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
(Total 2 marks)
21
Page 49 of 92Brookvale Groby Learning Trust
Some farmed salmon have a coloured additive in the food that they are given. This is a permittedadditive that improves the colour of the fish meat.
A sample of the colour is extracted from a salmon.
Explain how paper chromatography could be used to confirm that this is the permitted additive.
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
(Total 3 marks)
22
(a) Suggest why it is important to be able to identify the colour additives in food.
___________________________________________________________________
___________________________________________________________________
(1)
23
Page 50 of 92Brookvale Groby Learning Trust
(b) A brown colour used in sweets was analysed using chromatography. The results werecompared with those from E104 and E133.
What do the results tell you about the brown colour and its suitability for use in sweets?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(3)
(c) Once all the unsuitable colours are removed, the company claims that its sweets are now‘free from artificial colours’.
Does this mean that the sweets contain no additives? Explain your answer.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(Total 6 marks)
Page 51 of 92Brookvale Groby Learning Trust
The electrolysis of sodium chloride solution is an important industrial process. The apparatusshown below can be used to show this electrolysis in the laboratory.
24
(a) Name gas A. ________________________________________________________
(1)
(b) Chlorine is produced at the positive electrode. Describe and give the result of a chemicaltest to prove that the gas is chlorine.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(c) Chloride ions move to the positive electrode. Explain why.
___________________________________________________________________
___________________________________________________________________
(1)
(d) A small quantity of chlorine is added to drinking water. Explain why.
___________________________________________________________________
___________________________________________________________________
(1)
Page 52 of 92Brookvale Groby Learning Trust
(e) The solution around the negative electrode becomes alkaline. Name the ion which makesthe solution alkaline.
___________________________________________________________________
___________________________________________________________________
(1)
(Total 6 marks)
The diagram shows an outline of the periodic table.
Choose your answers only from the letters shown on the table above.
The periodic table on the Data Sheet may help you to answer this question.
Which element, A to F:
(a) is in Group 3;
___________________
(1)
25
(b) is a metal which floats on water and reacts violently to make an alkaline solution andhydrogen gas;
____________________
(1)
(c) is a gas which burns with a squeaky pop?
____________________
(1)
(Total 3 marks)
Hydrogen peroxide, H2O2, is often used as a bleach. It decomposes forming water and oxygen.
(a) (i) Write the balanced chemical equation for the decomposition of hydrogen peroxide.
______________________________________________________________
(3)
26
Page 53 of 92Brookvale Groby Learning Trust
(ii) Give a test for oxygen.
Test _________________________________________________________
Result of test __________________________________________________
______________________________________________________________
(2)
(b) The rate of decomposition of hydrogen peroxide at room temperature is very slow.Manganese oxide is a catalyst which can be used to speed up the decomposition.Complete the sentence.
A catalyst is a substance which speeds up a chemical reaction. At the end of the
reaction, the catalyst is ________________________________________________
(1)
(c) Two experiments were carried out to test if the amount of manganese oxide, MnO2 affectedthe rate at which the hydrogen peroxide decomposed.
(i) Complete the diagram to show how you could measure the volume of oxygen formedduring the decomposition.
(2)
Page 54 of 92Brookvale Groby Learning Trust
(ii) The results are shown in the table.
Time in minutes 0 0.5 1 1.5 2 2.5 3 3.5
Volume of gas in cm3
using 0.25 g MnO2
0 29 55 77 98 116 132 144
Volume of gas in cm3
using 2.5 g MnO2
0 45 84 118 145 162 174 182
Draw a graph of these results. The graph for 0.25 g MnO2 has been drawn for you.
(3)
(iii) Explain why the slopes of the graphs become less steep during the reaction.
______________________________________________________________
______________________________________________________________
______________________________________________________________
(2)
Page 55 of 92Brookvale Groby Learning Trust
(iv) The same volume and concentration of hydrogen peroxide solution was used for bothexperiments. What two other factors must be kept the same to make it a fair test?
1. ____________________________________________________________
______________________________________________________________
2. ____________________________________________________________
______________________________________________________________
(2)
(Total 15 marks)
Acids and bases are commonly found around the home.
(a) Baking powder contains sodium hydrogencarbonate mixed with an acid.
(i) When water is added, the baking powder releases carbon dioxide. How could youtest the gas to show that it is carbon dioxide?
Test _________________________________________________________
Result of test __________________________________________________
(2)
27
(ii) Complete and balance the chemical equation for the reaction of sodiumhydrogencarbonate with sulphuric acid.
NaHCO3 + H2SO4 → ____________ + ____________ + _________
(2)
(b) Indigestion tablets contain bases which cure indigestion by neutralising excess stomachacid.
(i) One type of indigestion tablet contains magnesium hydroxide. This base neutralisesstomach acid as shown by the balanced chemical equation.
Mg(OH)2 + 2HCl → MgCl2 + 2H2O
Write a balanced ionic equation for the neutralisation reaction.
______________________________________________________________
(2)
Page 56 of 92Brookvale Groby Learning Trust
(ii) How does the pH in the stomach change after taking the tablets?
______________________________________________________________
(1)
(c) Ammonium sulphate is used as a lawn fertiliser.
Using ammonia solution, describe how you would make the fertiliser ammonium sulphate.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(3)
(Total 10 marks)
Methane CH4 contains the elements carbon and hydrogen only. A student wanted to find outwhich new substances are produced when methane is burned. The student set up the apparatusshown below.
28
Page 57 of 92Brookvale Groby Learning Trust
(a) Which gas in the air reacts with methane when it burns?
___________________________________________________________________
(1)
(b) Name the liquid collected.
___________________________________________________________________
(1)
(c) Name the gas which turns limewater milky.
___________________________________________________________________
(1)
(d) When methane burns an exothermic reaction takes place. What is meant by an exothermicreaction?
___________________________________________________________________
___________________________________________________________________
(2)
(Total 5 marks)
The gases produced when coal burns are cooled by ice and then bubbled through limewater.
29
(a) Complete these sentences.
(i) The coal is reacting with ________________________ when it burns.
(ii) During burning, elements in the coal are converted to compounds
called ______________________________
(2)
Page 58 of 92Brookvale Groby Learning Trust
(b) Choose words from this list to complete the sentences.
carbon carbon dioxide sulphur sulphur dioxide
sodium water
(i) Liquid X is a compound made from hydrogen and oxygen.
It is called _____________________________________________________
(ii) Sulphur dioxide is an acidic gas. It is given off when coal burns, because coal
contains the element _____________________________________________
(iii) Most fuels are compounds of hydrogen and __________________________
(3)
(c) Burning coal is an exothermic reaction.
Explain what “exothermic” means.
___________________________________________________________________
___________________________________________________________________
(1)
(d) (i) Which gas turns limewater cloudy?
______________________________________________________________
(ii) Which element in the coal is oxidised to form this gas?
______________________________________________________________
(2)
(Total 8 marks)
Choose words from this list to complete the sentences,
ammonia carbon dioxide hydrogen nitrogen
electrical heat solar sound
30
(a) In air, the two most common gases are oxygen and _______________________ .
(b) When natural gas burns, energy is released mainly as _____________________ .
(c) When natural gas burns, a gas is produced which turns limewater milky.
The gas is _____________________________ .
(Total 3 marks)
Page 59 of 92Brookvale Groby Learning Trust
A student investigated heating metal carbonates.
The student used the apparatus in the figure below.
The student’s results are shown in the table below.
Metalcarbonate
Colourbeforeheating
Colourafter
heating
Mass beforeheating in g
Mass afterheating in g
SolutionA
Coppercarbonate
Green Black 12.4 8.0Turnscloudy
Potassiumcarbonate
White White 13.8 13.8Stays
colourless
Zinccarbonate
White White 12.5 8.1Turnscloudy
(a) Use the correct answer from the box to complete the sentence.
black green white
The colour of copper oxide is _____________ .
(1)
31
(b) Solution A is used to test for carbon dioxide.
Carbon dioxide turns Solution A cloudy.
What is the name of Solution A?
___________________________________________________________________
(1)
(Total 2 marks)
Page 60 of 92Brookvale Groby Learning Trust
Scientists in the 16th century used the symbol shown in Figure 1 for gold.
Figure 1
Gold
The scientists thought platinum was made from gold and silver, so they used the symbol for goldin the symbol for platinum. The symbol for platinum is shown in Figure 2.
Figure 2
Platinum
(a) Gold and platinum are elements.
What is meant by the term element?
___________________________________________________________________
___________________________________________________________________
(1)
32
(b) Why is it incorrect to represent platinum as shown in Figure 2?
___________________________________________________________________
___________________________________________________________________
(1)
Page 61 of 92Brookvale Groby Learning Trust
(c) Scientists now use a formula such as Ag2O to represent a substance.
What does the formula Ag2O tell you about this substance?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(2)
(Total 4 marks)
Page 62 of 92Brookvale Groby Learning Trust
A student investigated heating metal carbonates.
The student used the apparatus in the figure below.
The student’s results are shown in the table below.
Metalcarbonate
Colourbeforeheating
Colourafter
heating
Mass beforeheating in g
Mass afterheating in g
Limewater
Coppercarbonate
Green Black 12.4 8.0Turnscloudy
Potassiumcarbonate
White White 13.8
Zinccarbonate
White White 12.5 8.1
(a) Explain the observations seen when heating copper carbonate.
Include the names of the substances produced.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(3)
33
Page 63 of 92Brookvale Groby Learning Trust
(b) (i) Potassium carbonate did not decompose when heated.
State why.
______________________________________________________________
______________________________________________________________
(1)
(ii) Complete the table above to show the results you would expect the student to obtain.
(3)
(Total 7 marks)
Fire dancers use firesticks to make flame patterns.
One end of the firestick is soaked in kerosene.The kerosene is lit and burns with a yellow flame.
Kerosene is a mixture of hydrocarbons.
34
(a) Complete the following sentence.
A hydrocarbon is made up of only two elements, _____________________ and carbon.
(1)
Page 64 of 92Brookvale Groby Learning Trust
(b) A student investigated the products formed when kerosene burned.
Diagram 1 shows the apparatus the student used.
Diagram 1
(i) The limewater turns cloudy.
Name the gas that turns limewater cloudy.
______________________________________________________________
(1)
(ii) Name the colourless liquid collected in the U–tube.
______________________________________________________________
(1)
Page 65 of 92Brookvale Groby Learning Trust
(c) Kerosene is obtained from crude oil.
Crude oil is separated into fractions.
The process is called fractional distillation.
Diagram 2
Use only information from Diagram 2 to help you to answer these questions.
(i) Which of the named fractions has the lowest boiling point?
______________________________________________________________
(1)
(ii) Which of the named fractions is the most viscous (thickest)?
______________________________________________________________
(1)
(iii) Use the correct word from the box to complete the sentence.
fuels metals plastics
All the fractions listed in Diagram 2 can be used as ___________________ .
(1)
Page 66 of 92Brookvale Groby Learning Trust
(d) Crude oil is separated by fractional distillation.
The statements, A, B, C, D and E, describe how different fractions are obtained from crudeoil.
A crude oil is heatedB hydrocarbons condenseC hydrocarbon vapours enter the fractionating columnD hydrocarbons with higher boiling points condense near the bottom of the columnE crude oil vaporises
Complete the sequence below. Put the statements, A, B, C, D and E, in the correct order toshow how crude oil is separated into fractions.
The first and last boxes have been completed for you.
(2)
(Total 8 marks)
Fire dancers use firesticks to make flame patterns.
One end of the firestick is soaked in kerosene.The kerosene is lit and burns with a yellow flame.
35
(a) Kerosene is a mixture of hydrocarbons.
Which elements are present in a hydrocarbon?
___________________________________________________________________
___________________________________________________________________
(1)
Page 67 of 92Brookvale Groby Learning Trust
(b) A student investigated the products formed when kerosene burned.
The diagram shows the apparatus the student used.
Describe and explain the observations you would expect the student to make.
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
(4)
(Total 5 marks)
Page 68 of 92Brookvale Groby Learning Trust
Mark schemes
(a) Flask11
(b) Fractional distillation1
(c) A – boiling
in this order1
B – condensing1
(d) Pentane1
(e) Formulation1
(f) the fuel is a pure compound1
and crude oil is a mixture
or
the fuel is made up of four hydrocarbons
allow crude oil contains a large number of compounds and the fuelcontains four
and crude oil could have many more1
(g) (35 + 37 + 37 / 3) = 36.331
361
allow (35 + 48 + 37 + 37 / 4 =) 39(.25) for 1 mark
[10]
(a) start line drawn in ink12
(so) line would run1
start line below solvent level1
(so) samples would wash off1
Page 69 of 92Brookvale Groby Learning Trust
(b) red and blue
both colours needed1
(c) yellow1
travels furthest up the paper1
(d) distance moved by red ink 13 ±1
measurements in cm max 1 mark for mps 1 and 21
distance from start line to solvent front 44 ±11
correct substitution1
allow ecf from Table 4
correct answer1
range if correct is 0.27 to 0.33
to 2 significant figures1
(e) moves further or nearer the top of the paper1
[13]
(a) Safe to drink13
(b) To remove undissolved solids1
(c) the gas is chlorine / Cl21
which sterilises water1
(d) as distance between steel increases strength of concrete decreases1
change above and change below 1.0 cm separation is compared and described
must refer to graph values for this mark1
[6]
(a) (medicine is) a mixture and
(designed as) a useful product1
4
Page 70 of 92Brookvale Groby Learning Trust
(b) sugar / flavouring1
to make it taste better
or
colouring
to make it look more attractive1
(c) C8H9NO2
any order of elements1
1511
(d) mass of acetylsalicylic acid = 0.3 g1
=
method mark – divide mass by Mr1
= 0.00167 (mol)
allow 0.0016666(66)1
1.67 × 10-3 (mol)
correct answer with or without working scores 4 marks
allow ecf from steps1, 2 and 31
[9]
(a) mobile phase / solvent moves through paper15
and carries substances different distances1
which depend on their attraction for paper and solvent
allow which depend on solubility in solvent and attraction to paper1
Page 71 of 92Brookvale Groby Learning Trust
(b) Level 2 (3–4 marks):A relevant and coherent description which provides a clear analysis of the chromatogram.The response makes logical links between the points raised and uses sufficient examplesto support these links.
Level 1 (1–2 marks):Simple statements are made which demonstrate a basic attempt to analyse thechromatogram. The response may fail to make logical links between the points raised.
0 marks:No relevant content
Indicative content• black ink is a mixture• because more than one spot• contains blue, red and yellow• because Rf values / positions match• does not contain green• contains an unknown• which is insoluble• yellow is most soluble or has highest Rf value, blue is least
4
(c) both measurements from artwork for 1 mark (1.3 ± 0.1 cm and 5.3 ± 0.1 cm)1
correct equation used for 1 mark1
0.25 ± 0.021
accept 0.25 ± 0.02 without working shown for 3 marks
allow ecf from incorrect measurement to final answer for 2 marks
[10]
(a) start line drawn in ink16
so it will run / dissolve in the solvent / split up
allow mixes with the spots1
spots under solvent or solvent above spots / start line1
so they will mix with solvent or wash off paper or colour the solvent or dissolve in thesolvent
1
(b) (i) contains A and E1
Page 72 of 92Brookvale Groby Learning Trust
and one other (unknown substance)
if no other marks awarded, an answer saying it is made up of threecolours gains 1 mark
1
(ii) 45 or 46
allow any value from 45 to 461
18
allow any value from 16 to 20
award 1 mark if numbers correct but in cm1
(iii) 0.40
allow ecf from (b)(ii)
ignore units1
(c) fast red
allow ecf from (b)(iii)1
has same Rf value
allow none of them, as none has the same Rf value for 2 marks1
(d) any one from:
• more accurate• more sensitive• uses small quantities of samples• quicker / faster / more rapid• can link to mass spectrometer (MS)
1
[12]
(a) (i) copper is less reactive than hydrogen or copper is unreactive17
(ii) Zinc and dilute hydrochloric acid1
(b) (gas) syringe1
(c) (i) 35
allow 31
Page 73 of 92Brookvale Groby Learning Trust
because not close to others
accept it is much lower than the others
ignore references to trends or patterns
dependent on the first mark1
(ii) (49 + 50 + 48) / 3
= 49
correct answer with or without working gains 2 marks1
allow ecf from anomaly identified in (i) for 2 marks:
• Exp 1 anomalous gives 43.3
• Exp. 2 anomalous gives 44
• Exp. 4 anomalous gives 44.7
answer of 45.5 or 46 (anomaly not excluded) gains 1 mark
correct working excluding anomaly but with wrong answer gains 1mark
1
(iii) so that a mean can be calculated
accept improves accuracy of the mean or so anomalies can beidentified / discarded or to reduce effect of random errors
ignore makes it a fair test
ignore reliability, validity, repeatability, reproducibility1
(d) (i) idea of mixing with oxygen / air, letting air / oxygen in
accept converse1
(ii) H2O
do not accept incorrect additional products1
balancing 2 … (1) … 2
allow fractions or multiples
dependent on first mark1
[11]
Page 74 of 92Brookvale Groby Learning Trust
(a) (i) (phosphoric) acid
allow phosphoric1
(ii) H+ / hydrogen (ion)
if ion symbol given, charge must be correct1
(b) (i) pencil1
so it will not run / smudge / dissolve
ignore pencil will not interfere with / affect the results
or
because ink would run / smudge / dissolve
ignore ink will interfere with / affect the results1
(ii) any three from:
reference to spots / dots = max 2
allow colouring for colour• 3 colours in Cola
allow more colours in cola or fewer colours in fruit drink• 2 colours in Fruit drink• one of the colours is the same• two of the colours in Cola are different• one of the colours in Fruit drink is different
allow some of the colours in the drinks are different• one of the colours in Cola is the most soluble
accept one of the colours in Cola has the highest Rf value3
(c) different substances travel at different speeds or have different retention times
accept different attraction to solid
ignore properties of compounds1
(d) (i) Is there caffeine in a certain brand of drink?1
(ii) any two from:
• cannot be done by experiment• based on opinion / lifestyle choice• ethical, social or economic issue
accept caffeine has different effects on different people2
[11]
8
(a) time from when the heating is started until19Page 75 of 92Brookvale Groby Learning Trust
the limewater turns cloudy / milky1
(b) (i) the temperature was not high enough
accept the copper carbonate had not started to decompose / react
accept it takes time to heat up the copper carbonate1
the bubbles of gas were air
accept no carbon dioxide produced1
(ii) the copper carbonate was decomposing / reacting
accept the temperature was high enough to cause decomposition /a reaction
1
so carbon dioxide was produced
allow correct word / symbol equation1
(iii) copper oxide was produced
allow correct word / symbol equation1
because the copper carbonate had completely decomposed / reacted
ignore all of the carbon dioxide had been given off1
[8]
(a) additive110
(b) colour 3 is a mixture of colours 1 and 2
any two from:
accept E-number or additive instead of colour
ignore comments about height / level1
• colour 1 is made up of only one colour / dye
• colour 2 is made up of only one colour / dye
• colour 3 is made up of two colours / dyesormore colours (than colours 1 and 2)
2
[4]
Page 76 of 92Brookvale Groby Learning Trust
(a) any two from:
ignore reference to taste / shelf-life / sales etc
• improve the colour / appearance
• additives are permitted / not banned / listed on the label
• link between additives and hyperactivity not proved
• maintain the low cost of the drink or natural colours would make the drink costmore
allow cheaper if qualified2
11
(b) have a control group / placebo or test children before any drink given1
give a drink to at least 3 groups or give a drink at least 3 times1
give each additive to different group / children / at different times1
observe / monitor / compare behaviour of group / children1
(c) (i) so that there would be trust / respect / no bias1
(ii) compare the colours / spots from the orange drink with those of the (three)additives
accept diagram of chromatogram(s) with spots for E102, 104, 110and sample from the orange drink
1
there should be no matching colours / spots1
[9]
(a) (i) any two from:
• bubbles / effervescence / fizzing
ignore hydrogen / gas produced• lithium disappears / gets smaller
allow dissolvesdo not allow melts / burns
• lithium moves on the surface of the water
ignore floats• (universal indicator) turns blue / purple
2
12
(ii) 2
left-hand side correct1
Page 77 of 92Brookvale Groby Learning Trust
2
right-hand side correct
allow multiples for full credit1
(iii) light / burn, which will give a (squeaky) pop / explosion1
(iv) all have 1 electron in their outer shell / energy level
allow have the same number of electrons in their outer shell /energy level
1
(b) They react with oxygen1
They have low melting points1
(c) (i) electronic structure [2,8,8] is drawn
incomplete inner shells scores a maximum of 1 mark1
charge is +
allow [2,8,8]+ for 1 mark1
(ii) because (in potassium) the outer shell electron is further away from the nucleusor because potassium atoms are larger than sodium atoms
it should be clear that the candidate is referring to the outer shellelectron: if this is not clear a maximum of 2 marks can be awarded
1
therefore the outer shell electron is less strongly attracted to the nucleus or ismore shielded from the attraction of the nucleus and so the outer shell electronin potassium is more easily lost
1
3 marks can be scored for answering the question in terms ofsodium
1
[13]
(a) (i) magnesium oxide113
(ii) decomposition1
(b) (i) bar chart1
(ii) more1
Page 78 of 92Brookvale Groby Learning Trust
(iii) limewater1
turns cloudy / milky
accept forms a white precipitate1
[6]
(a) limewater or calcium hydroxide solution114
(reacts with carbon dioxide and) turns cloudy / milky
linked to first point
if no other mark awarded ‘puts out lighted splint’ gains 1 mark1
(b) (i) any two from:
• same volume / amount of the acids
• concentration of the acids
• temperature
• same surface area / size / mass / amount of calcium carbonate
• same measuring equipment2
(ii) any three from:
• (after about 4 minutes) the sulfuric acid stops reacting or nitric acid continues toreact
accept more CO2 with nitric acid at any time after 4 minutes
• (initially) the reaction with sulfuric acid is faster
• (the reaction stops) because calcium sulfate is a solid
allow sulfuric acid produces a solid
• (the reaction continues) because calcium nitrate is soluble / in solution /aqueous
allow nitric acid produces an (aqueous) solution
• because the calcium sulfate prevents the sulfuric acid reacting with the calciumcarbonate
• (the rate is faster) because sulfuric acid contains two hydrogens3
[7]
(a) (i) chromatography115
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(ii) 3 / three1
(iii) the colour / E104 is not on the same level as any of the colours in the food
accept E104 does not match1
(b) (i) to improve the appearance of the food
ignore adds yellow / colour
ignore taste / flavour1
(ii) further / or different tests (for harmful effects) or obtain more evidence(that it is harmful)
allow do a survey / study1
[5]
(a) (i) react
allow neutralise
allow bubbles / fizzes
accept produces gas / CO2F
ignore rises1
16
(ii) stop reacting / producing
stops on its own is insufficient allow stop working / bubbling / fizzing1
the (hydrochloric) acid / (calcium) carbonate is used up
accept because the (calcium) carbonate has neutralised the(hydrochloric) acid
OR
have been used up (1)
the graph line becomes horizontal / levels out (1)
OR
stays the same / no change (1)
ignore reference to graph line
no further reaction (1)1
(iii) bubble the gas through limewater / calcium hydroxide solution
allow (add) limewater
test must be correct to gain result mark1
Page 80 of 92Brookvale Groby Learning Trust
(the solution) goes cloudy
allow milky1
(b) advantage > Quarrying limestone provides building materials,employment and new road links
1
disadvantage > Quarrying limestone releases dust, and lorriesrelease carbon dioxide from burning diesel fuel
1
[7]
(a) (i) prevent evaporation of solvent
allow prevent loss of solvent
allow to support the (chromatography) paper1
17
(ii) ink dissolves in the solvent
allow ink ‘runs’ / spreads or pencil does not ‘run’ / spread
allow ink would affect the result / mixes with colours
or
carbon / graphite does not dissolve in the solvent
accept pencil for carbon / graphite1
(b) (i) 41
(ii) no mark for ‘no / don’t know’ ,
ignore numbers
any one from:
• because not all colours match
• not all colours are safe
• some colours could be unsafe
• some colours travelled higher (than safe colours)1
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(c) (i) any two from:
ignore reliable / precise
• rapid / quick
• accurate
• sensitive or detects very small quantities
accept small sample2
(ii) separates1
(iii) identifies solvents / compounds / substances
accept (relative) molecular mass
accept formula mass
accept Mr
accept relative mass
accept molecular ion peak1
[8]
(a) (improve) appearance
allow add colour
allow these food colourings have not been proven to causehyperactive behaviour in young children
do not accept taste / flavour / preservatives
ignore reference to E-numbers1
18
(b) X1
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(c) any three from:
• S contains six / 6 colourings
• P contains five / 5 colourings
if neither of first 2 bullet points given allow 1 mark for S containsmore colours than P or converse
• both S and P contain the same
five / 5 colourings
• both contain W and Y
• both sweets (may) cause hyperactivity
ignore unsafe
• neither contain X and Z3
[5]
(a) to improve the appearance of the drink119
because they are permitted colours1
(b) (i) chromatography1
(ii) three / 31
(iii) because one colour / spot / E102 matched1
because the other / two colours / spots / E104 and E110 did not match
if no other mark awarded allow because the drink did not containE104 and E110 or because the drink contained E102 for 1 mark
accept only E102 matched for 2 marks1
[6]
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(i) any two from:
• A has four colours(*)
• B has three colours(*)
(*) if first two bullets not statedaccept A has more colours (than B) or B has less colours (than A)for 1 mark only
• A / B have two colours the same
• B has one different colour2
(ii) chromatography1
[3]
20
drinks / colours B and C are safe1
drinks / colours A and D are not safe
accept a pair of one safe colour and one not safe colour identifiedfor 1 mark
accept A, B, C and D all contain one safe colour for 1 mark
ignore references to shading1
[2]
21
use of solvent / solution / water / any named solvent1
separates / carries colour(s) / dye(s)
allow any idea of movementeg runs / moves
1
match against Rf value / known chromatogram / similar patternor comparison to permitted additive / colour
removal of coloured additive from salmon does not gain any marks
ignore reasons for separation
maximum 2 if technique clearly doesn’t work1
[3]
22
(a) check if safe to eat / healthy
or
permitted
accept references to allergies / medical problems1
23
Page 84 of 92Brookvale Groby Learning Trust
(b) any three from:
accept dye for colour
• made up of two colours / dots
• contains an unknown colour / dot
• contains a harmful colour
• contains E104 / quinoline yellowor does not contain E133 / brilliant blue
• further analysis needed3
(c) ignore No or Yes but No must be implied
there could be other additives (in the sweets)
accept any other type of additives but not colourings1
could still contain / use / add natural colours
accept non-artificial for natural
or
named natural colours1
[6]
(a) hydrogen
accept H2
do not accept H1
24
(b) litmus paper / Universal Indicator paper / pH paper
allow any suitable named indicator1
bleached / turns white or loses its colour
do not accept bleached cloth / leaves etc.
allow second mark unless incorrect indicator given
allow starch iodide paper (1)goes black / blue black (1)
allow potassium iodide solution (1) goes brown / orange / blackprecipitate (1)
1
(c) because they have a negative charge or opposite charges attract
accept (because) it is Cl–
accept chlorine, Cl or chlorine ions has a negative charge
do not accept Cl– on its owndo not accept Cl2 o.e. has negative charge
1
Page 85 of 92Brookvale Groby Learning Trust
(d) kill bacteria / germs, etc. or sterilise / disinfect
accept destroys bacteria etc.ignore clean / purify water (owtte)do not accept just gets rid of bacteria
1
(e) hydroxide (ion)
accept OH–
1
[6]
(a) F
accept indium / In1
25
(b) C
accept sodium / Na1
(c) A
accept hydrogen / H / H21
[3]
(a) (i) H2O2 reactant correct
ignore any state symbols1
H2O + O2 products correct1
2H2O2 → 2H2O + O2 balanced
accept correct multiple1
26
(ii) glowing splint1
relights
accept ‘bursts into flame’
do not accept a lighted splint burns brighter or faster1
(b) unchanged
accept not used up or left (behind)1
(c) (i) gas syringe or measuring cylinder either with scale drawn or labelled1
the apparatus as drawn would work1
Page 86 of 92Brookvale Groby Learning Trust
(ii) correct plotting of points
one mark to be deducted for each error2
best fit graph line drawn (single line drawn)1
(iii) concentration of hydrogen peroxidedecreases
accept less particles of hydrogen peroxide to collide
do not accept hydrogen peroxide gets used up1
rate of reaction decreases
accept reaction gets slower1
(iv) any two from:
• temperature
• pressure
• division of catalyst or manganese oxide
do not accept any other factors2
[15]
(a) (i) test: limewater
accept calcium hydroxide solution1
result: ‘goes’ cloudy
accept white or milky
do not accept misty or chalky test must be correct before resultmark can be considered
1
27
(ii) 2 NaHCO3 + H2SO4 →
Na2SO4 + (2) H2O + (2) CO21
correctly balanced1
(b) (i) H+ + OH–
1
→ H2O
deduct one mark if incorrectly balanced
accept H3O+ instead of H+ then 2H2O needed for balance1
Page 87 of 92Brookvale Groby Learning Trust
(ii) pH increases
accept numerical indication1
(c) addition of sulphuric acid1
correct use of an indicator
accept idea of forming a neutral solution1
crystallisation (of neutral solution)
accept description using evaporation1
[10]
(a) oxygen/O2
for 1 mark1
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(b) water/H2O
for 1 mark1
(c) carbon dioxide/CO2
(if symbols are used they must be correct)
for 1 mark1
(d) gives out
for 1 mark1
heat or energy (2 independent marks)
for 1 mark1
[5]
(a) (i) oxygen (not air)
(ii) oxides/monoxides/dioxides
for 1 mark each
Do not allow specific examples2
29
(b) (i) water
(ii) sulphur
(iii) carbon
for 1 mark each3
Page 88 of 92Brookvale Groby Learning Trust
(c) gives out/releases heat/energy
for 1 mark1
(d) (i) carbon dioxide
(ii) carbon
for 1 mark each
(allow correct symbols/formulae)2
[8]
(a) nitrogen / N2
[Do not allow N or N2] for 1 mark
(b) heat
for 1 mark
(c) carbon dioxide / CO2
for 1 mark
[3]
30
(a) black131
(b) limewater
accept calcium hydroxide (solution)1
[2]
(a) contains only one sort of atom132
(b) platinum is not a compound / mixture / alloy
or
platinum is an element so should have own (unique) symbol
or
symbol shown represents 2 different sorts of atom
allow platinum is (an element so) not made of gold and silver1
Page 89 of 92Brookvale Groby Learning Trust
(c) it contains two silver ions and one oxide ion
maximum of 1 mark if mention of being mixed together / covalentlybonded
allow silver atoms for silver ions
allow oxygen atom / ion for oxide ion
allow for 1 mark:
it is silver oxide
or
it is made of silver and oxygen
or
it is a compound
or
correct ratio of 2:1 atoms / ions for incorrect element(s)2
[4]
(a) (black) copper oxide formed
explanation must be linked to correct observation1
33
loss in mass is due to carbon dioxide / gas production1
limewater cloudy shows carbon dioxide produced1
(b) (i) any one from:
ignore references to reactivity
• (bunsen burner flame) not hot enough (to decompose potassiumcarbonate)
accept temperature not high enough (to decompose potassiumcarbonate)
• not all Group 1 carbonates decompose
allow potassium is in Group 11
(ii) potassium carbonate:
(mass) 13.8 g1
(limewater) colourless
accept no change for colourless
ignore clear1
Page 90 of 92Brookvale Groby Learning Trust
zinc carbonate:
(limewater turns) cloudy
Metalcarbonate
Mass afterheating in g
Limewater
Potassiumcarbonate
13.8 colourless
Zinccarbonate
cloudy
1
[7]
(a) hydrogen
allow H2
H must be uppercase and number a subscript1
34
(b) (i) carbon dioxide
allow CO2
letters must be uppercase and number a subscript1
(ii) water
allow H2O
letters must be uppercase and number a subscript ignore steam1
(c) (i) petrol
allow petroleum / refinery gases1
(ii) fuel (oil)
allow bitumen1
(iii) fuels1
(d) A → E → C → B → D2 if in correct order
any of following gains 1 mark if overall order is incorrect E before C
or
C before B2
[8]
Page 91 of 92Brookvale Groby Learning Trust
(a) hydrogen and carbon
both elements in either order needed for mark
any additional elements negates the mark1
35
(b) colourless liquid / condensation in U tube
ignore ice melts1
(because) water produced1
lime water goes cloudy1
(because) carbon dioxide produced1
[5]
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