Question 1

Using OIL RIG, oxidation is:

Accepted Answer

Loss of electrons — OIL RIG: Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons).

Question 2

The oxidising agent in a redox reaction is the substance that:

Accepted Answer

Is itself reduced, causing another substance to be oxidised — The oxidising agent gains electrons (is reduced) and in doing so removes electrons from — oxidises — another species.

Question 3

In the reaction $Zn(s) + Cu^{2+}(aq) \rightarrow Zn^{2+}(aq) + Cu(s)$, which species is oxidised?

Accepted Answer

Zn, since its oxidation number increases from 0 to +2 — Zn goes from oxidation number 0 (uncombined element) to +2 (as $Zn^{2+}$), an increase, which is oxidation (loss of 2 electrons).

Electrochemistry

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