One of the reactions in the rechargeable lead/acid battery is shown. $$\[ \mathrm{Pb}(\mathrm{s})+\mathrm{PbO}_{2}(\mathrm{~s})+4 \mathrm{H}^{+}(\mathrm{aq})+2 \mathrm{SO}_{4}{ }^{2-}(\mathrm{aq}) \rightarrow 2 \mathrm{PbSO}_{4}(\mathrm{~s})+2 \mathrm{H}_{2} \mathrm{O}(\mathrm{l}) \]$$ Which statement about this reaction is correct? A Lead is both oxidised and reduced. B Lead is neither oxidised nor reduced. C Lead is oxidised only. D Lead is reduced only.

Chemistry

IGCSE&ALevel

CAIE

Exam No：9701_m24_qp_12 Year：2024 Question No：11

Answer:

6.1.1 calculate oxidation numbers of elements in compounds and ions

6.1.2 use changes in oxidation numbers to help balance chemical equations

6.1.3 explain and use the terms redox, oxidation, reduction and disproportionation in terms of electron transfer and changes in oxidation number

6.1.4 explain and use the terms oxidising agent and reducing agent

6.1.5 use a Roman numeral to indicate the magnitude of the oxidation number of an element