Question

Write down the chemical formulae for the molecular compounds Aluminum oxide.

Answer 1

Step 1: Identifying the symbols of the elements

Aluminum oxide is made up of the ions aluminum and oxide. Their symbols are,

aluminum = $\mathrm{Al}$ and oxide= $\mathrm{O}$

Step 2: Identifying the valency of the elements

Valency of aluminum is $+3$ as it is a trivalent cation.

Valency of oxide is $-2$ as it is a bivalent anion.

Step 3: Cross-over the valencies with symbols

Thus, the formula for Aluminum oxide is ${\mathrm{Al}}_2{\mathrm{O}}_3$.