Page 253 - Chemistry

(iii) NH 4NO 3 N 2O + 2H 2O
(iv) Fertilizer/expose
(c) (i) G or G
-
(ii) E 2+ (aq) + 2OH (aq) E(OH) 2(s)

-
19. a) i) G// G 2(g) Not G
It has the highest potential OR highest reduction potential  1 mark
ii) G and N or G 2(g) // N (g)  1 mark

iii)

20. a) (i) Cathode – steel
Anode – Carbon / graphite
+
(ii) To lower the melting P hence reducing cost of heating the salt.
(iii) To prevent the two products from recombining.
(iv) Cathode
+
-
Na (l) + e Na (l)
Anode
-
2 Cl (l) Cl 2 (g) + 2 e-
(v) less dense than electrolyte/ has low density
b) (i) quantity = 6.42 X 10 60 = 3852
(ii) 3852c province 2.74
2X 96000 “ (2 X 96000) X 2.74
3852
= 136.58

+
-
21. .a) i) H (aq) + e ½ H 2

ii) E cell = 0.76 + 0.54 = +1.3 volts

3+
iii) I. Fe
II. Zn
3+
IV. Fe ion
3+
2+
-
0
2 Fe + 2 e 2 Fe E = + 0.77
0
2 I I 2g + 2e E = - 0.54

2+
-
3+
0
2 Fe + 2I 2Fe + I 2 E = + 0.23
(aq)
(aq)
(aq)

22. a) i) Chlorine Has a higher reduction potential
ii) +1.36 2.36 = +3.72

b) i) P and S
ii)
iii) +1.50 – 0.44 + + 1.94

c) Q = 4 X a6 X 60 = 3840C
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