Mark Scheme (Results) Summer 2015
Mark Scheme (Results)Summer 2015Pearson Edexcel International GCSEChemistry (4CH0) Paper 1CScience Double Award (4SC0) Paper 1CPearson Edexcel Level 1/Level 2 CertificateChemistry (KCH0) Paper 1CScience (Double Award) (KSC0) Paper 1C
Edexcel and BTEC QualificationsEdexcel and BTEC qualifications are awarded by Pearson, the UK’s largestawarding body. We provide a wide range of qualifications includingacademic, vocational, occupational and specific programmes for employers.For further information visit our qualifications websites at www.edexcel.comor www.btec.co.uk. Alternatively, you can get in touch with us using thedetails on our contact us page at www.edexcel.com/contactus.Pearson: helping people progress, everywherePearson aspires to be the world’s leading learning company. Our aim is to helpeveryone progress in their lives through education. We believe in every kind oflearning, for all kinds of people, wherever they are in the world. We’ve beeninvolved in education for over 150 years, and by working across 70 countries, in100 languages, we have built an international reputation for our commitment tohigh standards and raising achievement through innovation in education. Find outmore about how we can help you and your students at: www.pearson.com/ukSummer 2015Publications Code UG041123All the material in this publication is copyright Pearson Education Ltd 2015
General Marking Guidance All candidates must receive the same treatment. Examiners mustmark the first candidate in exactly the same way as they mark thelast. Mark schemes should be applied positively. Candidates must berewarded for what they have shown they can do rather than penalisedfor omissions. Examiners should mark according to the mark scheme not accordingto their perception of where the grade boundaries may lie. There is no ceiling on achievement. All marks on the mark schemeshould be used appropriately. All the marks on the mark scheme are designed to be awarded.Examiners should always award full marks if deserved, i.e. if theanswer matches the mark scheme. Examiners should also beprepared to award zero marks if the candidate’s response is notworthy of credit according to the mark scheme. Where some judgement is required, mark schemes will provide theprinciples by which marks will be awarded and exemplification may belimited. When examiners are in doubt regarding the application of the markscheme to a candidate’s response, the team leader must be consulted. Crossed out work should be marked UNLESS the candidate hasreplaced it with an alternative response.
Questionnumber1abiAnswersix circles separated from each otherNotesMarksAccept minimum of 4 complete circlesIgnore size and shape of circlesIgnore arrows and other symbols implyingmovementIgnore a patternReject any touching circlesReject circles joined by bondsNo penalty for half-circles at edges ofsquare1iiB(They move randomly in the liquid state)1iiiD(melting)1iB(condensing and evaporating)1iiD(N2(l))1Total 5 marks
Questionnumber2abAnswerM1C(Bromine has a darker colour than air)M2D(Bromine vapour diffuses upwards)iCiiM1Marks21ammonia (particles/molecules)travels/diffuses faster / further in same time(than hydrogenchloride)M2Notes(because of) lower MrDo not penalise ammonia atoms /ammonium (ions) / ammonia solution inplace of ammoniaIf incorrect choice in (i), then no marks in(ii)If no answer in (i), mark onIf C appears in (ii), mark can be awarded in(i)2Accept smaller/lighter / ammonia lessdenseReject ammonia molecules etc less denseIgnore references to kinetic energyAccept reverse argument for hydrogenchloride / hydrochloric acid for both M1 andM2Total 5 marks
Questionnumber3AnsweraMarksAccept answers in either orderM1bright / white / blinding AND flame / light(OWTTE)bcNotesM2white solidC(a basic oxide formed from a metal)iblueiihydroxide (ion) / OH– / HO–2Ignore shines / glows / sparksAccept burns brightlyReject other coloursAccept smoke / powder / ash / deposit inplace of solidReject precipitate in place of solidIgnore greyIgnore name of product and equationIgnore references to decrease in amount ofmagnesium / heat given off1Ignore shadesIgnore purpleReject all other coloursMark (i) and (ii) independentlyIgnore OH11Total 5 marks
Questionnumber4AnswerCaCl2(aq) H2SO4(aq) CaSO4(s) 2HCl(aq)abNotesMarksAll four must be correct to scoreDo not penalise upper case letters1M1filter paper in filter funnelDo not penalise inappropriate size2M2everything else correctNot essential that funnel touches flaskReject beaker/tube for M2Ignore labelsIgnore relative sizesciCa2 / calcium (ion)iicalcium sulfate/CaSO4 is partially/slightly solubleReject Ca with incorrect or missing chargeMark (i) and (ii) independently1ORcontains unreacted/excess calcium chloride/CaCl2(solution)1Accept unreacted/excess calcium ions
Questionnumber4dNotesMarksiwhite precipitateAccept solid / ppt / ppte / suspension in placeof precipitateReject other coloursReject other observations eg fizzingIgnore cloudy/milky/grey1iisilver chlorideAccept correct formulaIgnore incorrect formulaAward both marks if both answers in either (i)or (ii)1(hydrochloric/sulfuric) acid / H thereORsolution acidicAccept because there are no other ions thatcould form a precipitateAccept no carbonate/hydroxide (ions)1M1Reject methods that refer to filtrate /solution/crystallisationIgnore other named solventsiiieAnswerwash/rinse (with water)M2leave it (to dry) / leave in a warm place /place in an oven / place in desiccator / heat it /dry with absorbentpaper (egkitchen/filter/blotting)2Accept leave on a window ledgeIgnore evaporate it / boil itAward 1 mark for both M1 and M2 correct butin wrong orderTotal 10 marks
Questionnumber5abcAnswerNotesH12C5gap between C5 and H12namesCnH2n 2Marks1iC5H12AcceptIgnoreIgnoreIgnoreiiCH2BrAccept elements in any orderIgnore molecular formulaIgnore 2CH2BrPenalise inappropriate use of upper or lower case letters ornumbers(eg CH2Br / CH2BR / CH2Br)1iR and UAccept in either order1iiD(CnH2n)1C(compound R compound Q)1
Questionnumber5dAnswerM1NotesMark M1 and M2 independentlyMarks2Accept Br atoms in any positions so long as on different carbonatomsM2(1,2-)dibromoethaneIgnore any numbersAccept ethylene dibromideeiiiIgnore balancing in equationIgnore molecular formulabromomethaneiiiUV or ultraviolet (light/radiation)ivD(substitution)11Accept sunlightIgnore all references to heat and temperatureIgnore references to pressure11
Questionnumber5fiAnswerM1setting out division of each % by Ar d 0/3 if division by any atomic numbers/ wrong way up / multiplication used3Do not penalise roundings or minor misreads of% values (eg 56.7 for fluorine)Do not penalise use of Fl in (i)If molecular masses used for H and/or F, loseM1 but M2 and M3 can be awarded:using 2 and 38 gives C2H2Fusing 2 and 19 gives CHFUsing 1 and 38 gives C2H4FWorking required for these answersM2 subsumes M1M2simplest whole number ratio (1:2:1 or ratioshown innotes for M1)M3iiC2H4F2CH2FAccept elements in any orderAward 3 marks for correct final answer with noworkingAccept elements in any order1Do not accept C2H4Fl2Total 15 marks
Questionnumber6abAnswer(A)refinery econtaining)carbon and hydrogen/C and H(atoms/elements)Reject atom/element/ion/mixture in place ofcompound/molecule/substanceReject compound/molecule/substance in place ofatom/elementIgnore references to bonds / long chainsM2Accept other terms with same meaning, eg solely /exclusively / justonlyMarksM2 DEP on mention of carbon and hydrogen/C and H andno other element2
Questionnumber6cAnswerNotes(fuel oil molecules/it/they)Accept converse statements about gasolineM1have higher boiling pointsIgnore reference to melting pointsM2are darker (in colour)Ignore stronger / more intense (colours)If specific colours stated, award M2 if valid comparison,eg gasoline is yellow and fuel oil is brown, fuel oil isbrownerM3have higher viscosities / aremore viscousAccept thicker/stickier/flows less easily, etc in place ofmore viscousIf gasoline, accept thinner/runnier/flows more easily, etcin place of less viscousMust be a comparison, eg not enough to say fuel oil has ahigh boiling point unless also a statement that gasolinehas a low boiling pointMAX 2 if no comparisonAccept reference to fractions near the top/up the columnin place of gasolineAccept reference to fractions near the bottom/down thecolumn in place of fuel oilMarks3
diiisilica / silicon dioxide / SiO2ORalumina / aluminium oxide / Al2O3Accept aluminosilicate(s) / zeolitesM1C2H4Accept in either orderM2C3H61Ignore silica oxide and alumina oxideAward 1 mark for C4H8 and CH22
Questionnumber6eAnsweriinsufficient/lack of air / oxygen OWTTEiicarbon monoxide / COiiidecreases capacity of blood (cells) tocarry oxygenORstops blood (cells) from carrying oxygenNotesAccept oxygen not in excessReject no oxygenMarks11Accept CO combines with haemoglobin / formscarboxyhaemoglobinAccept CO displaces/replaces oxygen in haemoglobinIgnore CO combines with red blood cellsIgnore references to suffocation / lack of oxygen in lungsstopping breathing / gas exchangeIgnore just affects haemoglobinReject destroys haemoglobinMark all parts independently1
Questionnumber6fiiiAnswerNotesM1sulfur dioxide AND sulfur trioxidein correct orderAccept names with correct oxidation statesM2sulfuric acidIgnore dilute / concentratedIgnore hydrogen sulfate / hydrogensulfateM1acid rainAccept makes lakes acidic / lowers pH of lakesM2specific adverse effect on /crops/named exampleeg dies/stunted growth/harmed/damaged/poisonedIgnore deforestationIgnore leaching mineralsfishfish/aquatic animals/pond life/marine life/named exampleeg dies/stunted growth/harmed/damaged/poisonedIgnore references to just animalsAcceptlimestonelimestone/marble reacts/corrodes/is eaten awayNOT just buildingsIgnore rusts or physical process such as erosion /weathering/ wearing away / dissolvingAccept destroys for adverse effect in all of aboveTotal 17 marks
Questionnumber7AnswerNotesMarksaA(addition)1bA(a molecule used to make a polymer)1ciiipropene1M1chain of two carbons joined by single bondAND both continuation bondsM2one CH3 group in any positionAND three H atoms2Do not penalise bond to H of CH3Reject any structure with double bondAllow multiple repeat units if correctThree or more CH2 groups linked together scores0/2Ignore brackets and subscripted ndAccept Cl in any positionIgnore bond anglesIgnore brackets / n1
Questionnumber7eiiiAnswerNotesMarksM1(polymer) breaks down / decomposes /decaysDo not penalise compound / object / molecule /substance in place of polymerReject element in place of polymerIgnore rots / degrades / digests / disintegratesIf reference to not breaking down etc, only M2can be awardedM2Accept biologically / naturallyby bacteria / microbes / microorganisms /decomposers /enzymesinert(ness) / unreactive / OWTTE2M2 DEP on M1 or near missIgnore do not react with named chemicalIgnore references to bond strengths / bondbreaking1Total 9 marks
t reference to one of these: number of colours(pink to colourless) end point/colour change (accept neutralpoint)Examples:phenolphthalein has only two colours / only onecolour change/ negative statement eg does not have a range ofcolours/ UI has several colours/more than one colourchange1sharp / definite / sudden / quick / not gradual /needs only one drop/ converse for UIdM1(after)answer)24.15 (only thisM2(before)answer)2.30M321.85(added)3Award 1 mark for both burette readings correct butin wrong order(only thisCQ on after and before readingsIn M3, penalise answer not to 2 dp unless penaltyalready applied in M2
Questionnumber8eAnswerNotesiticks in columns 2 and 4iiM126.30 26.402CQ on ticked resultsIf no results ticked, award M1 only if columns 2 and 4 averagedIf only one result ticked, no marks can be awarded in (e)M226.35CQ on results averagedAnswer must be to 2 dpM2 subsumes M1Marks12
fiiiiiiM10.18(0) 25(.0)1000M20.0045(0)In part (f): accept values in standard form, eg 4.5 10–3 do not accept unevaluated fractions, eg 0.0045 3 in (ii) do not penalise too many sig figs correct answer without working scores 2 marks in (i) and (iii) penalise missing use of 1000 in (i) and (iii) once only2Award 1 mark for 4.5(0.0045 3 ) 0.0015(0)CQ on answer to (i)1M10.0015 100028.3(0)CQ on answer to (ii)2M20.053(0)Award 1 mark out of 2 for 0.000053Award 1 mark out of 2 for 0.05If correct final answer obtained by omission of 1000 in both (i) and(iii), award marks of 1,1, 2Total 14 marks
Questionnumber9abiAnswerABCDsimple moleculargiant covalentgiant metallicgiant ionicM1electron transfer AND correct directionM2magnesium (atoms) lose 2 electronsM3(each) chlorine (atom) gains an electronNotesMarks4If any reference to sharing electrons, 0/3If any reference to covalent bonds, MAX 2Penalise atoms in place of electrons each time3Accept two chlorine (atoms) gain two electronsReject chloride in place of chlorineM2 and M3 both correct also scores M1iiM1for electronic configuration of Mg2 ionM2for electronic configuration of Cl– ionM3for both charges correctAccept any combination of dots and crossesCharges can be shown anywhere so long asthere is no ambiguityBrackets not essentialIgnore 2 before or after chloride ion0/3 for any diagram showing shared electronsIgnore diagrams showing electron transfer –mark only the ions formedPenalise missing inner shell(s) once onlyIf two Cl– ions shown, both must be correct3
Do not penalise empty third shell in Mg2 If only 2.8 etc notations without diagram, onlyM3 can be awarded
Questionnumber9AnswercNotesM1for 4 electrons in both C O bondsThese can be shown in a vertical or horizontal lineM2Marks2all other electrons correctM2 DEP on M1Accept any combination of dots and crossesIgnore inner electrons even if wrongIgnore circles around atomsNon-bonding electrons do not need to be paireddiM1positive ions / cationsM2delocalised electrons / sea ofelectronsM3crystal / lattice / regulararrangement / array/ giant structure / OWTTENot just ionsReject reference to protons/nuclei/atoms in place ofcations for M1, but M2 and M3 can still be awardedIgnore free electronsIgnore layers / planes / rows or similarAccept (electrostatic) attraction between positive ionsand electrons0/3 if reference to ionic bonding / covalent bonding /molecules/ intermolecular forces (eg van der Waals')3
Questionnumber9diiAnswerM1layers / sheets / planes / rowsAND(positive) ions / atoms / particlesM2slide (over each other)NotesMarks2Allow OWTTE, eg slip / flow / shift / roll / moveM2 DEP on mention of EITHER layers or equivalentOR mention of ions or equivalentDo not award M2 if protons / electrons / nuclei /molecules in place of ions, etcIf reference to ionic bonding / covalent bonding /molecules / intermolecular forces, no marksTotal 17 marks
sIgnore amount of solution for both, but accept amount incm3 for M1Reject volume of gasesAllow mass of solutionMarks2Ignore strengthIgnore temperature / pressureAccept in either orderbiB1iiD1cMark M1 and M2 independentlyM1filter (and dry) and weighsolid/A/itAccept separate/remove solid/A/it from reaction mixtureand weigh itM2mass is (still) 1g / mass isunchangedAccept reverse argument, eg if it was a reactant, the masswould decrease2
Questionnumber10dAnswerNotesM1 M2all five points plotted to nearest gridlinePoints at zero and 120 are not essential but must becorrect if plottedDeduct 1 mark for each error up to max 2iMarks3M3curve of best fitCurve does not need to be labelledIf curve correct but points not visible under curve,award M1 and M2Curve CQ on points plottedPenalise repeated straight line(s) joining points/ more than one curve visibleiiM1some indication on graphM2volume CQ on candidate curveeg vertical line up from 70sORhorizontal line to where line from 70s would meetcurveORcross on graph2Must be an integer (cm3)No marks if original curve usediiicurve steeper /gradient steeper/greaterORcurve levels off earlier / curve reaches100cm3 in shorter time / OWTTEAccept line for curveAccept graph is steeper1Accept answers that do not depend on graph but canbe obtained from the table of results, eg bigger volumein a shorter time, reaction stopped earlierTotal 12 marks
Questionnumber11aAnsweri(pressure) lowiifewer (gas) moles/molecules/particles on leftORfewer moles/molecules/particles of reactantsORforward reaction produces moremoles/molecules/particlesNotesMarks1Accept statement about numbers of moles /molecules,eg 3 on left and 5 on rightAccept more (gas) moles/molecules/particles onright/ more moles/molecules of products but not justmore products1Ignore references to favouring right handside/forward direction/endothermic reaction /equilibrium shifting toright/Le Chatelier’s principle/low pressure favours side with more molesIgnore references to rate / collisionsIf answer to (i) is high, no ECF in (ii)If no answer to (i), mark can be awarded in (ii)bi(temperature) highii(forward) reaction is endothermic / has positive H value/ absorbs heat1Accept reverse reaction is exothermic / hasnegative H value / gives out heatIgnore favours the endothermic reactionIgnore references to rate / collisionsIf answer to (i) is low, no ECF in (ii)If no answer to (i), mark can be awarded1
c H (value)/enthalpy change is small / smaller/ less (than for reactions 1 and 3)ORreaction not very exothermic / has lowestenthalpy changeAccept energy in place of enthalpyAccept closer to zeroReject H less negative / less exothermic / lessheat given outIgnore references to temperature change /pressureIgnore less energy / not a lot of energy needed1
Questionnumber11Answerdi(rate) increasesiiNotesIgnore references to yield / equilibrium / chances of collision in(i) and (ii)Mark M1 and M2 independentlyM1particles closer togetherM2particles collide morefrequentlyAccept more particles in a given volume/space/particles have less space/room (to move in)Ignore area in place of volume/spaceIgnore references to just numbers of gas moles/moleculesNot just more (successful) collisionsAccept more (successful) collisions per unit time / per second,etc0/2 if references to particles moving faster/having greaterenergyIf answer to (i) is decreases, no ECF in (ii)If no answer or ignored answer to (i), marks can be awardedMarks12
Questionnumber11eAnswerNotesMarksAccept working by mass ratio OR moles routesMass ratios:M1Mr (CH3OH) 32 AND Mr (CH3COOH) 60M2m(CH3COOH) 64 6032M33Award M1 for 32 and 60 seen anywhere,except as the result of incorrectcalculationsMark M2 and M3 consequentially on Mrvalues120 (kg)ORMoles:M1n(CH3OH) 64 000 32 2000 (mol)M2n(CH3COOH) 2000 (mol)M3(kg)m(CH3COOH) 2000 60 120 000 g / 120Allow working in 'kilomoles' even if molgiven as unit or no unit for intermediateanswers, eg64 32 2 (kmol/mol)CQ on M1CQ on M2Correct final answer with or withoutworking scores 3 marksAccept 120 000 g if unit shownTotal 11 marks
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Chemistry (KCH0) Paper 1C Science (Double Award) (KSC0) Paper 1C Edexcel and BTEC Qualifications Edexcel and BTEC qualifications are awarded by Pearson, the UK’s largest awarding body. We provide a wide range of qualifications including academic, vocational, occupational and specific programmes for employers. For further information visit our qualifications websites at www.edexcel.com or www .
CSEC English A Specimen Papers and Mark Schemes: Paper 01 92 Mark Scheme 107 Paper 02 108 Mark Scheme 131 Paper 032 146 Mark Scheme 154 CSEC English B Specimen Papers and Mark Schemes: Paper 01 159 Mark Scheme 178 Paper 02 180 Mark Scheme 197 Paper 032 232 Mark Scheme 240 CSEC English A Subject Reports: January 2004 June 2004
Matthew 27 Matthew 28 Mark 1 Mark 2 Mark 3 Mark 4 Mark 5 Mark 6 Mark 7 Mark 8 Mark 9 Mark 10 Mark 11 Mark 12 Mark 13 Mark 14 Mark 15 Mark 16 Catch-up Day CORAMDEOBIBLE.CHURCH/TOGETHER PAGE 1 OF 1 MAY 16 . Proverbs 2—3 Psalms 13—15 Psalms 16—17 Psalm 18 Psalms 19—21 Psalms
Examiners should mark according to the mark scheme not according to their perception of where the grade boundaries may lie. All marks on the mark scheme should be used appropriately. All marks on the mark scheme are designed to be awarded. Examiners should always award full marks if deserved, i.e. if the answer matches the mark scheme.
H567/03 Mark Scheme June 2018 6 USING THE MARK SCHEME Please study this Mark Scheme carefully. The Mark Scheme is an integral part of the process that begins with the setting of the question paper and ends with the awarding of grades. Question papers and Mark Schemes are d
the mark scheme should be used appropriately. All the marks on the mark scheme are designed to be awarded. Examiners should always award full marks if deserved, i.e. if the answer matches the mark scheme. Examiners should also be prepared to award zero marks if the candidate’s response is not worthy of credit according to the mark scheme.
Mark scheme for Paper 1 Tiers 3-5, 4-6, 5-7 and 6-8 National curriculum assessments ALL TIERS Ma KEY STAGE 3 2009. 2009 KS3 Mathematics test mark scheme: Paper 1 Introduction 2 Introduction This booklet contains the mark scheme for paper 1 at all tiers. The paper 2 mark scheme is printed in a separate booklet. Questions have been given names so that each one has a unique identifi er .
Aug 15, 2019 · Mark Scheme (Results) Summer 2019 Pearson International Advanced Subsidiary Level In Chemistry (WCH11) Paper 01 Structure, . perception of where the grade boundaries may lie. There is no ceiling on achievement. All marks on the mark scheme should be used appropriately. All th
the mark scheme, the own figure rule can be used with the accuracy mark. Of Own Figure rule Accuracy marks can be awarded where the candidates’ answer does not match the mark scheme, though is accurate based on their valid method. cao Correct Answer Only rule Accuracy marks will only be awarded if the candidates’ answer is correct, and in line with the mark scheme. oe Or Equivalent rule .
