Where circles have been placed round charges, this is for clarity only and does not indicate a requirement. ALLOW delocalised carboxylate.

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1 Question (a) Answer Mark Guidance Where circles have been placed round charges, this is for clarity only and does not indicate a requirement (i) ALLOW correct structural OR displayed OR skeletal formulae OR combination of above as long as unambiguous DO NOT ALLOW O Na OR -OO-Na ALLOW O (covalent bond) - ALLOW ONa ALLOW OONa OR OR ALLOW delocalised carboxylate (Na) (a) (ii) (omine) would be decolourised/turn (from orange/red/yellow/brown) to colourless IGNORE goes clear DO NOT ALLOW other colours for bromine OR white precipitate/solid/emulsion (formed) IGNORE cream precipitate DO NOT ALLOW salicylic acid turns colourless/decolourised IGNORE temperature/fumes (a) (iii) 2 ALLOW correct structural OR displayed OR skeletal formulae OR combination of above as long as unambiguous MUST be all correct to score mark ALLOW molecular formulae, i.e. 76O3 2 75O3

2 Question Answer Mark Guidance (a) (iv) ( 3 ) 2 O/ 3 (O) 3 /propan(-)2(-)ol AND acid/ / 2 SO 4 (catalyst) (b) (i) ALLOW correct structural OR displayed OR skeletal formulae OR combination of above as long as unambiguous 4 ALLOW 2-propanol DO NOT AEPT incorrect name or incorrect formula of alcohol IGNORE reflux/concentrated (acid) ALLOW mechanism with electrophile (Maximum 3 marks) No 2 dipole needed urly arrow to from ring OR from within the ring AND curly arrow - bond to IGNORE any equations involving a halogen carrier BUT DO NOT ALLOW intermediate with π-system covering less than half of ring: correct intermediate (with charge) curly arrow from to reform ring ALLOW charge anywhere inside the horseshoe orseshoe must have open end towards Apply ecf to error in structure of intermediate (M2)

3 Question Answer Mark Guidance ALLOW Kekulé mechanism as shown (Maximum 3 marks if is the electrophile) / - orrect products ( - may be shown in the first step) ALLOW double bonds in alternate arrangement

4 Question Answer Mark Guidance (b) (ii) (In salicylic acid) lone pair/pair of electrons on O()/phenol is ~ (partially) delocalised into the ring electron density increases/is high ORA 2 /electrophile is (more) polarised ORA 3 ALLOW diagram to show movement of lone pair into ring but delocalised ring must be mentioned ALLOW lone pair/pair of electrons on O()/phenol is (partially) drawn/attracted/pulled into delocalised ring IGNORE activates the ring ALLOW more electron rich DO NOT ALLOW charge density or electronegativity ALLOW (salicylic acid) attracts electrophiles more/more susceptible to electrophilic attack ALLOW 2 is (more) attracted OR 2 is not polarised by benzene OR induces dipoles (in bromine/electrophile) QW: delocalised/delocalized/delocalise etc. must be spelled correctly in the correct context at least once Delocalise(d) needed to score the first marking point (c) (i) Step Add NO 3 NO 3 2 O 4 ALLOW reagent mark if NO 3 in equation IGNORE 2 SO 4 (NOTE: 2 SO 4 not required with phenols) IGNORE concentrations of acids/temperature ALLOW correct structural OR displayed OR skeletal formulae OR combination of above as long as unambiguous Equations MUST be completely correct for one mark each

5 Question Answer Mark Guidance Step 2 Tin AND concentrated l 6 [] DO NOT ALLOW O (c) (ii) Nitrogen electron pair OR nitrogen lone pair accepts a proton/ DO NOT ALLOW nitrogen/n lone pair accepts hydrogen (proton/ required) ALLOW nitrogen donates an electron pair/lone pair to IGNORE N 2 group donates electron pair (c) (iii) compound A 2 ALLOW correct structural OR displayed OR skeletal formulae OR combination of above as long as unambiguous ALLOW N 2 l OR N 2 l DO NOT ALLOW N N OR N N l - DO NOT ALLOW N 2 -l (covalent bond) compound B

6 Question Answer Mark Guidance ALLOW Total 22 IGNORE bond angles DO NOT ALLOW more than one repeat unit unless correct repeat unit is indicated IGNORE brackets with n ALLOW any correct repeat unit ALLOW end bonds shown as DO NOT ALLOW if structure has no end bonds

7 Question er Marks Guidance 2 (a) In benzene, electrons OR π-bond(s) are delocalised ANNOTATIONS MUST BE USED ALLOW diagram with (π-bond) electrons AND delocalised labelled QW requires delocalised/delocalized spelled correctly and used in correct context IGNORE benzene has delocalised structure or ring In alkenes, π-electrons are OR π-bond is AND localised OR between two carbons ALLOW diagram with π-bond labelled ALLOW pi bond for π-bond π-bond OR π-electrons essential for this mark benzene has a lower electron density OR alkene/= has a higher electron density omparison essential IGNORE charge density DO NOT ALLOW electronegativity ALLOW for 2 ALLOW electrophile for 2 benzene polarises bromine / 2 LESS ALLOW benzene does NOT polarise bromine / 2 OR alkene/= polarises 2 OR benzene attracts bromine / 2 LESS ALLOW benzene does NOT attract bromine / 2 OR alkene/= attracts 2 OR benzene induces a weaker dipole in bromine / 2 4 ALLOW benzene does NOT induce dipole in bromine / 2 OR alkene/= induces dipole in 2

8 Question er Marks Guidance (b) ( ALLOW correct structural OR displayed OR skeletal formula ALLOW combination of formulae as long as unambiguous (ii) 6 NO EF from (i) (iii) Two of the three structures below with mark for each correct structure 2 ALLOW correct structural OR displayed OR skeletal formula ALLOW combination of formulae as long as unambiguous Structures must clearly show position of on benzene ring in relation to side chain ALLOW EF from (i) if BOT atoms on same carbon on side chain DO NOT ALLOW EF from (i) if EITER bromine has been substituted onto the benzene ring (iv) reaction : electrophilic addition reaction 2: electrophilic substitution 2 Total 0 ALLOW electrophile addition ALLOW electrophile substitution ALLOW other phonetic spellings for electrophilic, e.g. electrophylic, etc.

9 Question Answer Mark Guidance 3 (a) All 3 l 2 All 4 l ANNOTATIONS MUST BE USED l l l DO NOT ALLOW the following intermediate: l -ring must be more than /2 way up AND 'horseshoe' the right correct intermediate way up, ie gap towards with l curly arrow from -bond to l curly arrow from bond back to reform -ring correct products ALLOW sign anywhere inside the hexagon of intermediate All 4 All 3 l Note: st curly arrow should start within the ring or on the ring Note: ALLOW mechanism using Kekulé structures: 6 ALLOW st curly arrow starting within the hexagon ALLOW mechanism with l l----all 3 for st 2 marks, ie l l l l l All 3 Second curly arrow to either l or All 3 Note: If is used, DO NOT ALLOW st mechanism mark but all other marks available by EF

10 Question er Mark Guidance (b) (i) l Each mark is independent of the other 2 l 3 O 2 O st mark: reactants, correctly balanced, ie l l 3 O 2nd mark: product, (correctly balanced) 2 ie 2 O (ii) 6 (c) substitution/nitration/no 2 at different positions (on the ring) OR forms different isomers OR multiple substitution/nitration (d) In phenol, (lone) pair of electrons on O is (partially) delocalised into the ring QW: delocalised/delocalized/delocalise, etc must be spelt correctly in the correct context for benzene OR phenol at least once electron density increases/is high ORA l 2 /electrophile is (more) polarised ORA 3 Total 3 ALLOW 6 5 l for chlorobenzene ALLOW any unambiguous structure for l 3 O, e.g. l 3 O BUT.. DO NOT ALLOW l 3 O Standalone mark Standalone mark ALLOW examples, e.g. -chloro-2-nitrobenzene and -chloro-2-nitrobenzene ALLOW it for nitro group ALLOW examples, e.g. -chloro-2,3-dinitrobenzene IGNORE nitrate/no 3 ANNOTATIONS MUST BE USED ALLOW diagram to show movement of lone pair into ring but delocalised ring must be mentioned ALLOW lone pair of electrons on O is (partially) drawn/ attracted/pulled into delocalised ring IGNORE activates the ring DO NOT ALLOW charge density or electronegativity ALLOW l 2 is (more) attracted OR l 2 is not polarised by benzene OR induces dipoles (in chlorine/electrophile)

11 Question Expected Answers Marks Additional Guidance 4 a Bond length intermediate between/different from (short) = and (long) hydrogenation less exothermic than expected (when compared to hydrogenation for cyclohexene) Only reacts with 2 at high temp or in presence of a halogen carrier / resistant to electrophilic attack Please annotate, use ticks to show where marks are awarded b i compound A NO 2 if NO 2 in wrong position penalise here and EF for rest of b(i) and b(ii) 3 ALLOW all carbon carbon bonds the same length ALLOW hydrogenation less (negative) than expected ALLOW hydrogenation different from that expected DO NOT ALLOW halogenation/hydration ALLOW doesn t decolourise/react with/polarise 2 ALLOW doesn t undergo addition reactions (with 2 ) ALLOW any 4-nitro-,3-dimethylbenzene drawn in any orientation ALLOW NO drawn in any orientation compound B N 2 4 ALLOW any 4-amino-,3-dimethylbenzene drawn in any orientation EF amine of incorrect compound A (e.g. position of NO 2 or lack of methyl sticks/groups) compound N N ALLOW diazonium chloride salt of,3-dimethylbenzene EF diazonium salt/compound of incorrect compound B IGNORE l ion allow N N not allow N 2

12 Question Expected Answers Marks Additional Guidance ALLOW if charge is floating between the two Ns only if it is closer to the correct N allow not allow N N N N compound D O ALLOW any of O O O O - ALLOW O in place of O

13 Question Expected Answers Marks Additional Guidance ii Equation to show formation of NO 2 ion mark NO SO 4 3 O 2SO 4 NO 2 ALLOW NO 3 2 SO 4 2 O SO 4 NO 2 NO 3 2 SO 4 SO 4 2 NO 3 2 O NO 2 If NO 2 is in correct position do not penalise even if compound A in b(i) is not in correct position NO 2 mark 4 curly arrow from bond back to reform ring AND correct products NO 2 NO 2 5 ALLOW mark 2 curly arrow must be from,3- dimethylbenzene to NO 2 and EF for marks 3 and 4 DO NOT ALLOW intermediate -ring must be more than / 2 way up NO 2 mark 2 curly arrow from ring to NO 2 mark 5 - SO 4 mark 3 intermediate with ring broken in the correct place 2 SO 4 Link to compound A in part (i) cannot score full marks [in b(i) & b(ii)] if NO 2 is not adjacent to a methyl ALLOW 3 s shown ALLOW 3 O SO 4 2 O 2 SO 4 iii 2 No other correct response Total 3