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Which of the statements about the reaction below are incorrect?
2 PbO(s) + C(s) → 2Pb (s) + CO2(g)
(a) Lead is getting reduced.
(b) Carbon dioxide is getting oxidised.
(c) Carbon is getting oxidised.
(d) Lead oxide is getting reduced
(i) (a) and (b)
(ii) (a) and (c)
(iii) (a), (b) and (c)
(iv) All
Correct Answer: (i) (a) and (b).
Explanation: The simplest way of understanding oxidation and reduction is in terms of the gain and loss of oxygen. A redox reaction is where oxidation and reduction take place in the same chemical reaction.
Oxidation: It is the process of loss of electrons or an increase in oxidation state by a molecule, atom, or ion.
Reduction: It is the process of gain of electrons or a decrease in oxidation state by a molecule, atom, or ion.
In the given reaction,
$2PbO(s)+C(s)→2Pb(s)+CO_2(g)$...... (i)
+2 0 0 +4
According to the above reaction (i), Pb is the reduced substance, as Pb gains electrons.
Pb2+ + 2e– → Pb......(ii)
According to the above reaction (i), C is oxidized, as C loses electrons.
C → C2+ + 2e–......(iii)
Thus, PbO reduces to Pb and C oxidises into CO2
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