Question

A lithium oxide compound is represented by which formula? A) Li2O B) Li2O2 C) LiO D) LiO2

Answer 1

The correct answer would be A) Li2O :)

Answer 2

Answer: $Li_2O$

Explanation:

For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.  

Here Lithium is an element with atomic number of 3. Thus can lose one electron to attain stable configuration. Oxygen is an element with atomic number of 8 and thus can gain 2 electrons to attain stable configuration.

$Li:3:1s^22s^1$

$Li^{2+}:2:1s^2$

$O:8:1s^22s^22p^4$

$O^{2-}:10:1s^22s^22p^6$

Lithium having an oxidation state of +1 and oxide with oxidation state of -2 combine to form neutral $Li_2O$.