(c) electron rich ring or benzene or pi cloud repels nucleophile/ammonia Allow C–Cl bond is short/stronger than in haloalkane • C–Cl is less polar than in haloalkane • resonance stabilisation between ring and Cl • 1 [13] 6. (a) M1 Ester 1 If Ester 2, can score M3 only. 1 M2 peak at = 4.1 due to δ When marking M2 and M3, check any annotation of structures in the stem at the top of the page. 1 M3 = 4.1 peak is) quartet as adjacent / next to / attached to CH3 (δ 1 M4 Other spectrum quartet at = 2.1-2.6 (or value in this range) δ 1 (b) M1 Quaternary (alkyl) ammonium salt / bromide 1 M2 CH3Br or bromomethane Penalise contradictory formula and name. 1 M3 Excess ( CH3Br or bromomethane) Mention of acid eg H2SO4 OR alkali eg NaOH loses both M2 and M3. 1 M4 Nucleophilic substitution Can only score M3 if reagent correct. Ignore alcohol or ethanol (conditions) or Temp. 1 [8] (a) Reagent (1) P (ketone) S (2° alcohol) Acidified K2Cr2O7 no reaction (orange to) green Acidified KMnO4 no reaction (purple to) colourless I2 / NaOH Yellow ppt no reaction Named RCOOH with HCl or no reaction fruity or sweet smell H2SO4 Named RCOCl no reaction Misty fumes Allow names including Allow no change or nvc but penalise nothing or no observation potassium permanganate If 2 reagents added sequentially or 2 different reagents used Wrong or no reagent CE = 0 for P and S then CE = 0 Penalise incorrect formulae or incomplete reagent, such as K2Cr2O7 or acidified dichromate, but mark on. 1 1 1 (b) (1) and silver mirror / solid (1) Tollens’
(c) electron rich ring or benzene or pi cloud repels nucleophile/ammonia Allow • C–Cl bond is short/stronger than in haloalkane • C–Cl is less polar than in haloalkane • resonance stabilisation between ring and Cl 1 [13] 6. (a) M1 Ester 1 If Ester 2, can score M3 only. 1 M2 peak at δ = 4.1 due to When marking M2 and M3, check any annotation of structures in the stem at the top of the page. 1 M3 (δ = 4.1 peak is) quartet as adjacent / next to / attached to CH3 1 M4 Other spectrum quartet at δ = 2.1-2.6 (or value in this range) 1 (b) M1 Quaternary (alkyl) ammonium salt / bromide 1 M2 CH3Br or bromomethane Penalise contradictory formula and name. 1 M3 Excess ( CH3Br or bromomethane) Mention of acid eg H2SO4 OR alkali eg NaOH loses both M2 and M3. 1 M4 Nucleophilic substitution Can only score M3 if reagent correct. Ignore alcohol or ethanol (conditions) or Temp. 1 [8] (a) Reagent (1) P (ketone) S (2° alcohol) Acidified K2Cr2O7 no reaction (orange to) green Acidified KMnO4 no reaction (purple to) colourless I2 / NaOH Yellow ppt no reaction Named RCOOH with HCl or H2SO4 no reaction fruity or sweet smell Named RCOCl no reaction Misty fumes Allow names including potassium permanganate Wrong or no reagent CE = 0 Penalise incorrect formulae or incomplete reagent, such as K2Cr2O7 or acidified dichromate, but mark on. Allow no change or nvc but penalise nothing or no observation If 2 reagents added sequentially or 2 different reagents used for P and S then CE = 0 1 1 1 (b) Tollens’ (1) and silver mirror / solid (1)
a-level_paper_2_pp1_ms.docx