4.4, 4.5 HW MS
1.	(a)	nucleophilic addition	1

		4
 
(b)	(i)	2-hydroxybutanenitrile	1
(ii)		2

(allow 1 for amide even if not C4H7NO, i.e. RCONH2)
	(if not amide, allow one for any isomer of C4H7NO which shows geometric isomerism)
(c)	(i)		1

(ii)		1

(iii)	CH3CH=CHCOOH	1
[11]

2.	(a)	(i)	2, 3 – dimethylbutan – 2 – ol  (1)
(ii)	elimination  (1)
Mechanism 
 
(iii)	Structure 

Name of isomer 	2, 3 – dimethylbut – 1 – ene  (1)
Explanation 	loss of H+  or  H  (1)
	from end C also possible  (1)	10

(b)	(i)	Equation 
Name of mechanism 	addition – elimination (1)
Mechanism

(ii)	Type of reaction 	esterification  (1)
Reagent(s) 	CH3COOH  or  ethanoic acid  (1)
Conditions 	strong acid catalyst  (1)
	or  H2SO4  or  HCL	9
[19]

 
3.	(a)	(i)	propyl methanoate (1)
not propanyl
·	A wrong reagent or no reagent scores zero
·	An incomplete reagent such as silver nitrate for Tollens, or potassium dichromate loses the reagent mark, but can get both observation marks
·	penalise observations which just say colour change occurs or only state starting colour
(ii)	Reagent: NaHCO3 (1)
Observation with C: no reaction (1)
Observation with D: effervescence (1)	4
for C and D   NOT Tollens
Test	an identified (hydrogen) carbonate	acidified K2Cr2O7	acidified KMnO4	correct metal	UI or stated indicator	PCl5	
Observation with C	no reaction	goes green	goes colourless	no reaction	no change	no reaction	
observation with D	bubbles or CO2	no change	no change	bubbles or H2	red or correct colour
pH 3 – 6.9	(misty) fumes	
 
(b)	(i)	Reagent: pentan-2-one (1)
or 2-pentanone
but not pent-2-one or pentyl
(ii)	Reagent: Tollen’s or Fehling’s (1)
	Observation with E: no reaction (1)
	Observation with F: silver mirror or red ppt (1)	4
	for E and F
Test	Tollens	Fehlings or Benedicts	iodoform or I2/NaOH	acidified K2Cr2O7	Schiff’s	
observation with E	no reaction	no reaction	yellow (ppt)	no change	no reaction	
observation with F	silver or mirror or grey or ppt	red or ppt
not red solution	no reaction	goes green	goes pink	
 
(c)	 (1)	1
must be aldehyde. Allow C2H5 for CH3CH2 otherwise this is the only answer
[9]

4.	(a)	(i)	B:  propanoyl chloride (or consequentially on part (a) (ii)) (1)
C:  propanoic anhydride (or consequentially on part (a) (ii)) (1)	2
do not allow formulae
(ii)	effervescence / misty fumes / steamy fumes / fumes / 
solution becomes warm / fizzing     not just gas (1)	1 
(iii)	
 (1)	1
(the minimum necessary for the mark is C=O and C–N shown)
(iv)	 (1)	1
allow C2H5…..
(b)	(i)	methanol (1)
methyl propanoate (or consequentially on part (a) (ii)) (1)	2
do not allow formulae
(ii)	A:  in presence of (concentrated) sulphuric acid
/ H2SO4 / strong acid / gaseous hydrogen chloride or HCl
allow dilute H2SO4 (1)
heat / reflux    (but only if first mark awarded) (1)
allow 1 mark for acidic conditions / H+ and heat
B:  room temperature / in the cold / not heated / cooling not acid (1)
C:  heat / reflux not acid (1)	4
[11]

5.	(a)	(i)
 
(ii)	ester  (1)
solvent, flavourings  (1)
(iii)	conc H2SO4  (1)
in same physical state  (1)	6
(b)	C4H10O + 6O2 ® 4CO2 + 5H2O  (1)	1

(c)	(i)

(ii)	two H on carbon in double bond  (1)
(iii)	
cis but-2-ene  (1) trans but-2-ene	7
[14]

6.	(a)	Reagents 	NaBH4 (1)
Type of reaction 	reduction (1)	2 
(b)	(i)	Reagents(s)	K2Cr2O7 (1) H2SO4 (1)
Conditions 	reflux (1)
(ii)	CH3CH2CH2OH + 2[O] ® CH3CH2COOH + H2O (1)	4
(c)	Reagents  	HCN or NaCN/H+ (1)
Name of mechanism  	nucleophilicaddition (1)	2
(d)	(i)	mirror images (1)
(ii)	plane polarized light (1)
rotated in opposite directions (1)	3
 
(e)	(i)	Structure	
Name		propyl propanoate (1)
(ii)		3
 
(f)	CH3CH2CO or C3H6O + 4 O2  (1) ® 3 CO2 + 3H2O (1)	2
[16]

7.	(a)	(i)	correct graphical formula for tertiary alcohol
allow CH3 not C2H5 (1)
	2-methylbutan-2-ol / 2-hydroxy-2-methylbutane / 2-methyl-
2-hydroxybutane award name mark even if it follows 
incorrect formula (1)	2
(ii)	graphical formula of pent-1-ene (1)
	graphical formula of pent-2-ene (1)	2
	accept geometrical isomers of pent-2-ene if clearly shown to be different
(iii)	dehydration / elimination (1)	1
(iv)	no H atoms on C atom next to C–OH / three methyl groups on C (1)	1
(b)	(i)	ethanenitrile / ethanonitrile / methyl cyanide / 
cyanomethane / acetonitrile (1)	1
(ii)	any hydrolysis (1)	1
(iii)	CH3COCl  +  CH3NH2  ®  CH3CONHCH3  +  HCl
	for correct formula of methylamine / HCl product (1)
	overall correct (1)	2
[10]

8.	(a)	NaBH4 (1)	1
(b)	nucleophilic  addition (1)
 (1)	5
(c)	(i)	hexanedioic acid (1)
(ii)	C6H10O	®	C6H10O4
Mr = 98 (1)		Mr = 146 (1)
2.40 g	®	× 146 = 3.58 g (1)	4
[10]

9.	(a)	(i)	ethyl ethanoate

(1)	2
(ii)	esterification / condensation / addition - elimination (1)	1
 
(b)	(i)	aqueous / dilute sulphuric / hydrochloric acid (allow HCl(aq); H2SO4(aq) 
not water) (1)
temp. < 100° / warm / heat / reflux (this mark dependent on sensible
reagent) (1)
		2
(ii)	CH3COOC2H5 + H2O  ® CH3COOH + C2H5OH 
(allow C4H8O2, C2H4O2 but must have C2H5OH) (1)	1
(c)	(i)	sodium hydroxide / sodium carbonate / sodium hydrogen carbonate
(allow formula) (1)
room temperature / aqueous (2nd mark dependent on correct reagent) (1)	2
(ii)	ethanoic anhydride

(1)	2
(methyl groups can be shown as –CH3 but the C–C bond must be drawn)
(iii)	addition of water / hydrolysis (1)
(CH3CO)2O + H2O ® 2CH3COOH (1)	2 
(d)	(i)	ethanamide not ethylamide.

(1)	2
(ii)	ammonia (not if dilute implied) / ammonium carbonate /PCl5
followed by NH3 (allow formulae) (1)
heat or temperature < 100° (1)	2
(iii)	CH3CONH2 + HCl + H2O® CH3COOH + NH4Cl (1)	1
[17]

10.	(a)	(i)	An appropriate alkene; CH3CH2CHCH2 or (CH3)2CCH2	1
Isomer 1	1
Isomer 2	1
Position isomerism	1
Mechanism
	electrophilic attack and electron shift to Br (Unless H+ used)	1
carbocation	1
reaction with carbocation	1
[Allow mechanism marks for the alkene CH3CHCHCH3]
[Allow one mark if mechanism for minor product given] 
(ii)	An appropriate carbonyl; CH3CH2CHO	1
Mechanism	nucleophilic attack and electron shift to O	1
	anion intermediate	1
	reaction with anion	1
[Allow mechanism marks for the carbonyl (CH3)2CO]
	Isomer 1	1
Isomer 2	1
Optical isomerism	1
NB	Isomer structures must be tetrahedral
NB	Penalise “stick” structures once in part (a)
 
(b)	QoL  Large charge on carbonyl carbon atom due to bonding to O and Cl	1
Nucleophiles have electron pairs which can be donated	1
Equation	Species	1
	Balanced	1
[18]