Half-Reaction	$E^{\circ} (V)$
$F_{2} + 2 e^{-} \to 2 F^{-}$	$2.87$
$A g^{2} + e^{-} \to A g^{+}$	$1.99$
$C o^{3 +} + e^{-} \to C o^{2 +}$	$1.82$
$H_{2} O_{2} + 2 H^{+} + 2 e^{-} \to 2 H_{2} O$	$1.78$
$M n O_{4}^{-} + 4 H^{+} + 3 e^{-} \to M n O_{2} + 2 H_{2} O$	$1.68$
$2 e^{-} + 2 H^{+} + I O_{4}^{-} \to I O_{3}^{-} + H_{2} O$	$1.60$
$M n O_{4}^{-} + 8 H^{+} + 5 e^{-} \to M n^{2 +} + 4 H_{2} O$	$1.51$
$A u^{3 +} + 3 e^{-} \to A u$	$1.50$
$C l_{2} + 2 e^{-} \to 2 C l^{-}$	$1.36$
$O_{2} + 4 H^{+} + 4 e^{-} \to 2 H_{2} O$	$1.23$
$M n O_{2} + 4 H^{+} + 2 e^{-} \to M n^{2 +} + 2 H_{2} O$	$1.21$
$B r_{2} + 2 e^{-} \to 2 B r^{-}$	$1.09$
$N O_{3}^{-} + 4 H^{+} + 3 e^{-} \to N O + 2 H_{2} O$	$0.96$
$C l O_{2} + e^{-} \to C l O_{2}$	$0.954$
$2 H g^{2 +} + 2 e^{-} \to H g_{2}^{2 +}$	$0.91$
$A g^{+} + e^{-} \to A g$	$0.80$
$H g_{2}^{2 +} + 2 e^{-} \to 2 H g$	$0.80$
$F e^{3 +} + e^{-} \to F e^{2 +}$	$0.77$
$O_{2} + 2 H^{+} + 2 e^{-} \to H_{2} O_{2}$	$0.68$
$M n O_{4}^{-} + e^{-} \to M n O_{4}^{2 -}$	$0.56$
$I_{2} + 2 e^{-} \to 2 I^{-}$	$0.54$
$C u^{+} + e^{-} \to C u$	$0.52$
$O_{2} + 2 H_{2} O + 4 e^{-} \to 4 O H^{-}$	$0.40$
$C u^{2 +} + 2 e^{-} \to C u$	$0.34$
$A g C l + e^{-} \to A g + C l^{-}$	$0.22$
$C u^{2 +} + e^{-} \to C u^{+}$	$0.16$
$2 H^{+} + 2 e^{-} \to H_{2}$	$0.00$
$F e^{3 +} + 3 e^{-} \to F e$	$- 0.036$
$P b^{2 +} + 2 e^{-} \to P b$	$- 0.13$
$N i^{2 +} + 2 e^{-} \to N i$	$- 0.23$
$C d^{2 +} + 2 e^{-} \to C d$	$- 0.40$
$F e^{2 +} + 2 e^{-} \to F e$	$- 0.44$
$C r^{3 +} + e^{-} \to C r^{2 +}$	$- 0.50$
$C r^{3 +} + 3 e^{-} \to C r$	$- 0.73$
$Z n^{2 +} + 2 e^{-} \to Z n$	$- 0.76$
$2 H_{2} O + 2 e^{-} \to H_{2} + 2 O H^{-}$	$- 0.83$
$M n^{2 +} + 2 e^{-} \to M n$	$- 1.18$
$A l^{3 +} + 3 e^{-} \to A l$	$- 1.66$
$H_{2} + 2 e^{-} \to 2 H^{-}$	$- 2.23$
$M g^{2 +} + 2 e^{-} \to M g$	$- 2.37$
$N a^{+} + e^{-} \to N a$	$- 2.71$
$C a^{2 +} + 2 e^{-} \to C a$	$- 2.76$
$B a^{2 +} + 2 e^{-} \to B a$	$- 2.90$
$K^{+} + e^{-} \to K$	$- 2.92$
$L i^{+} + e^{-} \to L i$	$- 3.05$

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Which of the following reactions are reduction reactions? i. Cu2+ + 2e− → Cu ii. Fe → Fe3+ + 3e− iii. N2 + 3H2 → 2NH3 iv. C + O2 → CO2 [1 mark]

Which of the following reactions are reduction reactions?

i. ${C u}^{2 +}$ + 2 $e^{-}$ → Cu
ii. Fe → ${F e}^{3 +}$ + 3 $e^{-}$
iii. $N_{2}$ + 3 $H_{2}$ → 2 ${N H}_{3}$
iv. C + $O_{2}$ → ${C O}_{2}$

[1 mark]