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F324 HW 4 MS
1.	(a)	(i)	Diamino
two/2 amine groups (1)
	1,4
their position on the ring / numbering of carbons
around ring (or shown on a diagram) (1)	2
 (b)	(i)	reduction / redox (1)	1
(ii)	tin and HCl (1)
conc acid under reflux (1)	2
or H_2 gas + Ni/Pd catalyst
(iii)

H_2O as product (1)
and the equation balanced (1)	2
 (c)	(i)	accepts H^+ using the lone pair (on N) (1)
which is donated/forms a (dative) covalent bond (1)	2
either mark can be obtained with a good diagram
(ii)

correct structure with charges shown (1)(1)
one mark for either:	just one neutralised,
	both neutralised, but without Cl^–,
	both neutralised, but no charges shown	2
(iii)	hexane-1,6-diamine is a stronger base because:
	electrons move towards the N (due to the inductive effect)
(in hexane-1,6-diamine) (1)
	the lone pair from N is (partially) delocalised around the ring
(in diaminobenzene) (1)
	so the electron pair is more easily donated /
H^+ more easily accepted (in hexane-1,6 diamine) ora (1)	3
[14]

2.	(a)	(i)

	H_2O as product (1) balancing (1)	2
(ii)	reducing agent (1)	1
 (b)

(or as the ionic equation without Na^+ or Cl^–)
	C_6H_5NH_2 (1) balanced (1)	2

(c)	moles C_6H_5NO_2 used = 0.0300 (mol) (1)
	theoretical yield of C_6H_5NH_2 = 2.79(3) (g) (1) or ecf
	actual 72.1% yield = 2.014 (g) / (calculator value 2.013753) (1) or ecf
	to three sig figs = 2.01 (g) (1) or ecf	4
[9]

 3.	(i)

		3
(ii)	dye / colouring / indicator (1)	1
(iii)	phenylamine (1)
NaNO_2 / HNO_2 (1) + HCl (1)
< 10°C (1)
add to alkaline phenol (1)	5
[9]

 4.	sodium nitrite + HCl / nitrous acid (1)
	<10°C (1)
	 (1)
	phenol/named example (added to the products from above) AW (1)
alkaline conditions / OH^– (1)
	example of an azo dye that could be formed from phenylamine,
eg  (1)	6
[6]

5.	(i)	nitrous acid / HNO_2	1
(ii)
 (1)	1
(iii)	diazonium (ion /salt) (1)	1
(iv)	to prevent decomposition / it reacting (diazonium ion) is unstable AW	1
(v)	structure showing the amine coupled to the phenol or its salt – e.g.

–N=N– (1) rest of structure (joined by two nitrogens) (1)	2
[6]

6.	(a)	1^st stage
aromatic amine / named aromatic amine / structure (1)
sodium nitrite / nitrous acid (1)
HCl/H_2SO_4 (but not conc) /H^+ (1)
at <10°C (1)
	which forms a diazonium salt / ion (1)
if more than four are given, mark any wrong reagents, conditions first
	2^nd stage
the product from the first stage mixed with the phenol AW (1)
(in excess) hydroxide / alkali (1)	7
allow correct formulae for the reagents
(b)	(i)
 (1)	1
allow any benzene rings as well as N=N circled, as long as no other groups are
(ii)	…16… carbon and ……10….. hydrogen atoms
	(1)	(1)	2
 (c)	Na / NaOH / OH^– etc (1)	1

(d)

	(1)	(1)	2
allow 1 mark if they are both correct, but in the wrong boxes
only penalise a slip with SO_3^– Na^+ once
[13]

 7.	(i)	CH_3CH_2CH_2NH_2 (1)	1
(ii)

diazo link (1); rest of structure (1)	2
[3]

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