Giant ionic structures

2 marks · Easy

Lithium oxide (Li_2O) is an ionic compound formed from lithium ions (Li^+) and oxide ions (O^{2-}).

How many electrons in total are transferred from lithium atoms to oxygen atoms to form one formula unit of lithium oxide? Show your working.

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2 (±0)

Must show: 2 lithium atoms lose 1 electron each

Common mistakes: 1

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Marking points

M1 · 1 mark · Recognises two Li atoms involved; each loses 1 electron

A1 · 1 mark · Total electrons transferred is 2

Worked solution

Each Li atom loses 1 electron (Li → Li^+ + e^-).

There are 2 lithium atoms per formula unit (Li_2O).