9701 CHEMISTRY. 9701/12 Paper 1 (Multiple Choice), maximum raw mark 40

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1 CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International Advanced Subsidiary and Advanced Level MARK SCHEME for the March 206 series 970 CHEMISTRY 970/2 Paper (Multiple Choice), maximum raw mark 40 Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the March 206 series for most Cambridge IGCSE and Cambridge International A and AS Level components. IGCSE is the registered trademark of Cambridge International Examinations.

2 Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Number Key Question Number Key A 2 B 2 D 22 B 3 D 23 C 4 D 24 D 5 D 25 B 6 C 26 D 7 C 27 D 8 A 28 C 9 C 29 A 0 A 30 B C 3 B 2 D 32 D 3 C 33 B 4 D 34 C 5 A 35 A 6 B 36 D 7 A 37 C 8 B 38 B 9 A 39 A 20 D 40 C Cambridge International Examinations 206

3 CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International Advanced Subsidiary and Advanced Level MARK SCHEME for the March 206 series 970 CHEMISTRY 970/22 Paper 2 (AS Structured Questions), maximum raw mark 60 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the March 206 series for most Cambridge IGCSE and Cambridge International A and AS Level components. IGCSE is the registered trademark of Cambridge International Examinations.

4 Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (a) (i) greater attractive force OR greater force between nucleus and (outer) electrons proton number / atomic number / nuclear charge increases across period AND electrons occupy same shell / shielding roughly constant [] [] sulfur s electron removed from full (3p) orbital OR sulfur has two electrons in the same orbital [] electron electron repulsion (reduces energy required) [] (iii) sodium has mobile / free electrons / electrons free (to move throughout the structure) phosphorus is simple / covalent / molecular [] [] (iv) magnesium has two free / delocalised / outer / valence electrons per atom OR more free / delocalised / outer electrons than sodium [] [] (b) (i) A = Mg(NO 3 ) 2 B = H 2 C = NO 2 OR O 2 D = O 2 OR NO 2 [] [] [] [] [4] any Group I carbonate OR ammonium carbonate [] [] 2 (a) (i) = (mol) [] [] (i) 6 = (mol) [] [] Cambridge International Examinations 206

5 Page 3 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (iii) = (mol) [] [] (iv) M r of FeCO 3 = (6.0) = 5.8 (iii) M r (FeCO 3 ) =3.79g [] [] (iv) (v) 00% 5.00 = 75.9% [] [] (b) (i) 2Fe 3+ + Sn 2+ 2Fe 2+ + Sn 4+ species balancing [] [] 3 (a) (i) SnCl 2(aq) + 2HgCl 2(aq) SnCl 4(aq) + Hg 2 Cl 2(s) SnCl 2 AND 2 state symbols [] [] [0] three bonding pairs lone pair AND octet shape = (trigonal) pyramidal [] [] [] [3] Cambridge International Examinations 206

6 Page 4 Mark Schemee Cambridge International AS/ /A Level Marchh 206 Syllabus 9709 Paper 222 Question Answerr Markk Total sigma(σ) bond [] OR pi( (π) bonb d [] (b)( (i) forwardd and backward reactions occurring at same rate ORR thee ratee off forward and backward reactions are equal [] [] M = decrd reased yieldy d of products / lesss products formedd / ora M2 = left-hand side has fewer moles of gas ORR equilibriumm shifts to the left [] [] Cambridgee International ExamE minations 206

7 number of mol ecul es Page 5 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (c) E a with catalyst E a without catalyst [3] molecular energy M = correct Boltzmann curve M2, M3 any 2 from: line for both E a values or statement in text that catalyst lowers E a (catalyst) increases proportion/number of molecules/particles with energy activation energy so more frequent successful collisions [] [] [] Cambridge International Examinations 206

8 Page 6 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (d) (i) nucleophilic addition [] [] [5] correct dipole on carbonyl curly arrow from lone pair on CN AND from C=O to O correct intermediate curly arrow from lone pair on O to H + correct product [] [] [] [] [] [7] 4 (a) (i) C 4 H 0 C 4 H 9 [] [] [] [] (iii) [] [] (b) C 8 H 8 + 2½O 2 8CO 2 + 9H 2 O [] [] (c) sulfur dioxide would be produced on combustion (which contributes to) acid rain [] [] Cambridge International Examinations 206

9 Page 7 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (d) M = H has more / greater / stronger van der Waals / intermolecular forces than G / ora M2 = (because) H has more electrons (than G) M3 = J has hydrogen bonding (between molecules) M4 = strong(er) / great(er) forces require AND high / more energy to overcome [] [] [] [] [4] (e) NaOH(aq) [] [] [] 5 (a) (i) Q R [] [] S T [] [] [4] pent-3-en(e)-2-one OR 3-penten-2-one [] [] (iii) red / orange / yellow precipitate / solid [] [] Cambridge International Examinations 206

10 Page 8 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark Total (b) This question was discounted. M = decolourises bromine / cm = alkene M2 = absorption at 700 cm is C=O AND (very) broad absorption at cm is O H = carboxylic acid M3 = no cis-trans so terminal alkene OR chiral so contains a carbon atom with 4 different groups attached M4 = U is [] [] [] [] [4] [0] Cambridge International Examinations 206

11 CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International Advanced Subsidiary and Advanced Level MARK SCHEME for the March 206 series 970 CHEMISTRY 970/33 Paper 3 (Advanced Practical Skills), maximum raw mark 40 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the March 206 series for most Cambridge IGCSE and Cambridge International A and AS Level components. IGCSE is the registered trademark of Cambridge International Examinations.

12 Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question indicative material mark total (a) I All thermometer readings and mass of FA 2 recorded. Do not award if mass of FA 2 > 0.50 g. [4] II All temperatures recorded to 0.5 C. Award III and IV if within ranges given of supervisor s value. 2 (b) supervisor s T / C III IV 46.0 ± 5.0 ± ± 4.0 ± ± 3.0 ± ± 2.0 ± ±.0 ± 0.5 < 6.0 ± 0.5 I Axes labelled with units and uniform scale chosen to use more than half of each axis including 0 C above the highest recorded temperature. [4] II All recorded points plotted (minimum 9). III Appropriate lines of best fit drawn: best fit lines must be or a smooth curve; Points not on the line must be balanced on either side of the bestfit line and any points ringed or labelled as anomalous ignored. IV Lines extrapolated and correct value (within 0.5 C) of T read from graph. (c) (i) Correctly calculates Q = T from (b). [3] Correct expression for value of enthalpy change (c)(i) 24.3 = (ignore sign) mass in (a) 000 Negative sign and both answers recorded to 2 4 sig. fig. and no rounding to sig. fig. during calculation (unless exact value). (d) Incorrect, as the acid was in excess already. [] (e) Any one from: use lid or use specified extra insulation to reduce heat losses (by convection or conduction); use a pipette or burette for FA to reduce % error / as more accurately calibrated (owtte); use magnesium turnings / powder so reaction complete sooner as there is heat loss while magnesium ribbon is still reacting; use lid or plastic cup with higher walls to reduce acid spray; [] Cambridge International Examinations 206

13 Page 3 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question indicative material mark total 2 (a) I Initial and final burette readings and volume added recorded for rough titre and accurate titre details tabulated. II Initial and final burette readings recorded and volume of FA 4 added recorded for each accurate titration. All headings and units correct for accurate titrations: initial / final (burette) reading / volume or reading / volume at start / finish volume / FA 4 added / used or titre (cm 3 ) or / cm 3 or in cm 3 or cm 3 by every entry. [7] III All accurate burette readings are recorded to the nearest 0.05 cm 3. IV Has two uncorrected, accurate titres within 0. cm 3. V, VI and VII Award V, VI and VII for δ 0.20 cm 3 Award V and VI for 0.20 cm 3 < δ 0.30 cm 3 Award V for 0.30 cm 3 < δ 0.50 cm 3 (b) Mean titre correctly calculated from clearly selected values. Candidates must average two (or more) titres where the total spread is 0.20 cm 3. Working must be shown or ticks must be put next to the two (or more) accurate readings selected. The mean should normally be quoted to 2 d.p. rounded to the nearest 0.0. Note: the candidate s mean will sometimes be marked as correct even if it is different from the mean calculated by the examiner for the purpose of assessing accuracy. [] (c)(i) Correctly calculates and = (i) 0.00 (b) 000 [5] (iii) (iv) Correct expression (c) mol Mg = mass in (a) / 24.3 and mol HCl = (c)(iii) 25 / 000 mol HCl > 2 mol Mg (owtte) so the statement is correct. Allow ecf from incorrect (iii). Final answers (i), and (iii) to 3 or 4 sig. fig. and no rounding errors. Cambridge International Examinations 206

14 Page 4 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question indicative material mark total (d) Correct expression and answer to minimum 2 sig. fig. / correct (b) answer to minimum 2 sig.fig. and FA 3 (is measured more accurately). Allow ecf from (b) > 4.67 cm 3 then FA 4 (is measured more accurately). [] test observations FA 5 FA 6 NaOH no reaction / no change / no ppt white ppt, soluble in excess NH 3 no reaction / no change / no ppt white ppt, insoluble in excess HCl (warm) H + / MnO 4 blue solution brown gas / gas turning brown / gas turns blue litmus red / bleaches decolourises / purple to colourless or (solution) stays colourless no reaction / no change stays purple / pink or changes to purple / pink Ba 2+ / HCl no reaction / no change / no ppt white ppt, insoluble in HCl question indicative material mark total FA 5 is NaNO 2 ; FA 6 is Al 2 (SO 4 ) 3 ; FA 7 is Na 2 SO 3 (Na 2 S 2 O 5 ) 3 (a) Observations fully correct for both FA 5 and FA6 for NaOH. [8] Observations fully correct for both FA 5 and FA6 for NH 3. Observation of blue solution or brown gas with FA 5 and no reaction with FA 6 for HCl. Observations fully correct for both FA 5 and FA6 for H + / MnO 4. Observations fully correct for both FA 5 and FA6 for Ba 2+ / HCl. Cations: FA 5 unknown and FA 6 Al 3+ / aluminium Anions: FA 5 NO 2 / nitrite FA 6 SO 4 2 / sulfate Cambridge International Examinations 206

15 Page 5 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question indicative material mark total (b) (i) (Warm with) Al and NaOH and test gas with (damp) red litmus paper. [5] No reaction and not nitrate / N / same element as FA 5. BaCl 2 / Ba(NO 3 ) 2 and HCl / HNO 3 or H + / KMnO 4 / acidified potassium manganate(vii) or any named acid, (warm) and test gas with H + / KMnO 4. Ba 2+ and acid: white ppt, soluble in acid or H + / MnO 4 : solution decolourises / purple to colourless or acid and test gas with H + / KMnO 4 : gas (evolved with acid) which decolourises H + / MnO 4 (paper). FA 7 contains sulfite / SO 3 2 Cambridge International Examinations 206

16 CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International Advanced Subsidiary and Advanced Level MARK SCHEME for the March 206 series 970 CHEMISTRY 970/42 Paper 4 (A Level Structured Questions), maximum raw mark 00 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the March 206 series for most Cambridge IGCSE and Cambridge International A and AS Level components. IGCSE is the registered trademark of Cambridge International Examinations.

17 Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark (a) 2 (b) (i) sp 2 x = 60 / C 60 H 60 (c) (i) reaction : Cl 2 and UV light; reaction 2: Al Cl 3, Cl 2 (NOT aqueous); (free) radical substitution (iii) CCl 3 CCl 3 Cl Cl or Cl Cl Cl Cambridge International Examinations 206

18 Page 3 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark 2 (a) (i) Ca 2+ (g) + 2Cl (g) CaCl 2(s) (state symbols required) Ca 2+ (g) + 2Cl (g) (+ 2e ) 2 2 nd I.E of Ca st I.E of Ca EA of Cl 2 Atomisation/ H at of Ca E(Cl-Cl)/2 H at of Cl H latt o H f o CaCl 2 (s) (iii) H latt o = (2 349) = 2258 kj mol 3 (b) (higher temperature means that) particles have more energy; entropy (of the gas / system) increases because of an increase in the amount of disorder / randomness; 2 (c) (i) reaction sign of S o 2 CO(g) + O 2 (g) CO 2 (g) negative Mg(s) + ½O 2 (g) MgO(s) negative CuSO 4 (s) + 5H 2 O(l) CuSO 4.5H s O(s) negative NaHCO 3 (s) + H + (aq) Na + (aq) + CO 2 (g) + H 2 O(l) positive there is a reduction in the overall number of gaseous molecules (d) S o f = 386 (92 + (3 3)) = 99 (J K mol ) (e) (i) G o = H o T S o = 7 ((298 75) / 000) = (+) (kj mol ) 2 2 G o is positive and so the reaction is not spontaneous (at 298 K) Cambridge International Examinations 206

19 PagP ge 4 MarM k Schemee Cambridge International AS/AA LevL vel March 206 Syllabus 970 Paper 42 QuQ estion AnsA swer Markk 3 (a) Co Co o 2+ [Ar] 3d3 7 4s [Ar] 3d3 7 s 2 (b) Energy isolated ion tetrahedral complex (c) (i) [Co(Cl ) 3 (HH 2 O) O 3 3] Cl Cl Cll Co H 2 O OH H 2 OH H 2 ; Cl H 2 O Cl Co Cll OH 2 OH 2 2 (d) (i) [Pt(Cl ) 2 2(NH3) 3 2 ] M, M2: diagrams M3: names 2 cis-platinn / cis-diamminedichloroplatinum( (II)) trans-platin / trans-diamminedichloroplatinum(ii) (iii) (e) (i) (cis isomer) this can react / bond / bindd with DNA; which prevents replication of the strand / prevents cell division; M: formula M2: units (ecf from formula) K stab = [Cu(NH 3 ) 4 (H 2 O) 2 [Cu(H2O) ] 6 ][NHH 3 ] 4 mo ol 4 4 dm m 2 (large value of K stab shows that) thee tetramminee complex is more stable Cambridge International Examinations 206

20 PagP ge 5 MarM k Schemee Cambridge International AS/AA LevL vel March 206 Syllabus 970 Paper 42 QuQ estion AnsA swer Markk 4 (a) (i) st t order st t order (iii) rate = k[ CHH 3 CHO][ [OHH ] (iv) (v) (b) (i) (c) (d) mo ol dm m 3 s calculation from candidate s answer to t (iii) (expected answer = 6) rate-determining both reactant species are in step / rater e-determining step acid / proton donor / acidicc behaviour nucleophilic addition step: step explanation: M: both curly arrows M2: dipolee corrc rectly shown δ + δ (or per any suitable timee unit) Cambridge International Examinations 206

21 Page 6 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark 5 (a) (i) any metal with an E o value more negative than 0.4 V, e.g. Fe, Mn, Zn, Mg, Cr, Al R: Li / Na / K / Ca / Ba M: value of E cell correctly calculated (with correct sign) for metal named in (i) M2: E o cell is positive and so reaction is feasible (b) M: (Cr 2 O H + + 6e 2Cr H 2 O) E o = +.33 V (H 2 O 2 + 2H + + 2e 2H 2 O) E o = +.77 V E o cell = 0.44 (V) M2: E o cell (0.44 V) is positive (so the reaction is feasible) / E o (Cr 2 O 7 2 / Cr 3+ ) is less positive than E o (H 2 O 2 / H 2 O) (c) M: Cr 2 O 7 2 : ox.no Cr = +6 because 2 = 2 ox.no(cr) + (7 2) CrO 4 2 : ox.no Cr = +6 because 2 = ox.no(cr) + (4 2) M2: no change in oxidation number, so reaction is not redox (d) M: no. moles Cr deposited = / 52 = moles M2: deduction that 6 moles of e needed per mole of Cr / 2- reaction is Cr 2 O 7 + 4H + + 2e 2Cr + 7H 2 O M3: no. moles of e = = (0.25 t) / so t = ( ) / ( ) = 46.3 min / h / 2780 s Cambridge International Examinations 206

22 Page 7 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark 6 (a) identity or value V nitrogen or chlorine 3 X NO / NO 2 Cl O 2 / Cl O 3 m 2, 3,2,3, or 4 W sulfur Y SO 2 or SO 3 n 4, 3 (b) M: (white precipitate is BaSO 4 ) descending the group H sol becomes more endothermic / positive; M2, M3 any two from: H latt decreases / becomes more endothermic / becomes less exothermic H hyd decreases / becomes more endothermic / becomes less exothermic H hyd decreases more than H latt 2 Cambridge International Examinations 206

23 PagP ge 8 MarM k Schemee Cambridge International AS/AA LevL vel March 206 Syllabus 970 Paper 42 QuQ estion AnsA swer Markk 7 (a) (i) M: phenol is i more acidic than ethanol because the O H bond in phenol is weakenedd / thet phenoxide anion is stabilised / ethanol has an elee ctron donating group M2: p orbital / lone pairr off electronss on O can bee delod ocalisedd over / overlapss with ring reagent conditions Structure 3 HNO O 3 dilute, 5 C Br 2 aqueous (I: temperature) (iii) electrophilic substitution (b) (i) white precipitate / solidd between 0 C and 0 C (iii) M: double bonb nd between nitrogenn atoms M2: rest of mom lecule N N OHH (c) (i) CH H 3 CH H 3 C CHC H 3 CHH 2 NHN 2 CH H 3 CH H 3 N CH CH 3 CH 3 either onee or both CH 3 3 g roups circledd Cambridge International Examinations 206

24 PagP ge 9 MarM k Schemee Cambridge International AS/AA LevL vel March 206 Syllabus 970 Paper 42 QuQ estion AnsA swer Markk 8 (a) P Q R amidee ketone secondary alcohol Q = carbonyl and R = alcohol scores [] (b) (c) (i) see line on diad gram inn (b) (d) reagent observation 3 alkalinee iodine solution yellow ppt. formed universal indicatorr blue / purplee colour formed 2,4-dinitrophenylhydrazine yellow / orangee ppt formed Tollens reagent no reaction (e) (i) LiAl H H 4 (must be skeletal) (iii) CH CH H 3 H 3 C OH CH H 3 Cambridge International Examinations 206

25 Page 0 Mark Scheme Syllabus Paper Cambridge International AS/A Level March Question Answer Mark 9 (a) (i) polyester : Terylene / polylactic acid (PLA) / polyamide : nylon / Kevlar / Nomex water or hydrochloric acid / hydrogen chloride (b) (i) polymer biodegradable 2 A yes B yes C no D yes 2 HOCH 2 CH 2 OH and or equivalent,4-diacyl chloride or equivalent,4-diester (c) (i) V: it has two amine / NH 2 groups (which can be protonated) or it has an amine / NH 2 group on its side chain / R group four (TT, TU, UT, UU) (iii) hydrogen bonds; between the O / N atoms or named group (in the polypeptide) and water; or ion-dipole attractions; between NH 3 + / CO 2 and water; 2 Cambridge International Examinations 206

26 CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge International Advanced Subsidiary and Advanced Level MARK SCHEME for the March 206 series 970 CHEMISTRY 970/52 Paper 5 (Planning, Analysis and Evaluation), maximum raw mark 30 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the March 206 series for most Cambridge IGCSE and Cambridge International A and AS Level components. IGCSE is the registered trademark of Cambridge International Examinations.

27 Page 2 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question expected answer mark (a) M (apparatus mark) volumetric flask in range cm 3 ; [3] M2 mol propanone =.00 (flask volume / 000); e.g. mol of propanone = / 000 = mol M3 M2 58.0; e.g =.45 g (b) (i) B must be added before first or second reactant [] the reactants are A and C so one of these must be mixed last; or the reaction must not start before all three substances are present; [] (c) (i) (0 cm 3 ) pipette [] (d) (i) M NaHCO 3 will effervesce so when effervescence finishes it shows that all H + ions have been removed; M2 NaOH will react with I 2 / CH 3 COCH 3 / reactants; M mol I 2 = (0 / 00) (50 / 000) =.(00) 0 3 mol; M2 mol S 2 O 3 2 = = 2.(00) 0 3 mol; M3 volume 0.00 mol dm 3 S 2 O 3 2 = ( ) / 0.00 = 20(.0) cm 3 ; indicator = starch; colour change = blue-black to colourless; [3] (e) time and units of s; volume of thiosulfate and units of cm 3 ; (f) temperature; [] (g) (i) M (labels) x-axis = time y-axis = concentration of iodine M2 curved line decreasing from left to right starting from x = 0 Cambridge International Examinations 206

28 Page 3 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question expected answer mark idea of constant half-life: determine at least two half-lives from the graph and ensure that they are the same; or half-lives determined from the graph should be constant; or determine the gradient (rate) at different points on the graph and plot rate v. concentration to determine if the plot is linear and goes through the origin; [] (h) (incorrect and) half-life will still be constant; or temperature has no effect upon order (of reaction); [] 2 (a) M column amount of ethanol burned correctly completed M2 column energy transferred to the water correctly completed experiment number amount of ethanol burned / mol energy transferred to the water / kj (b) M at least eight correctly plotted points; M2 correct straight line; (c) experiment 6; [] (d) M co-ordinates, e.g. (0.006, 3.95) and (0.058, 5.62); M2 gradient correctly calculated from points, e.g. 32 (kj mol ); (e) because the reaction is exothermic; [] (f) (i) (( ) / 0.39) 00 = 0.256% and (0.05 / 40.0) 00 = 0.25%; [] Cambridge International Examinations 206

29 Page 4 Mark Scheme Syllabus Paper Cambridge International AS/A Level March question expected answer mark (total) errors in weighing do not account for the (large) error in enthalpy change determined; or heat loss (is more significant); [] Cambridge International Examinations 206

9701 CHEMISTRY. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers.

9701 CHEMISTRY. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. CAMBRIDGE INTERNATIONAL EXAMINATIONS Cambridge Advanced Subsidiary and Advanced Level MARK SEME for the March 06 series 970 EMISTRY 970/4 Paper 4 (A Level Structured Questions), maximum raw mark 00 This