A chemical equation is shown:

Al + O2 → Al2O3

According to the law of conservation of mass, how many atoms of oxygen exist in the products of this reaction?

The number of oxygen atoms are 6 atoms

Explanation

According to the law of mass conservation the number of reactant atoms is equal to number of product atoms.

For given equation to obey the law of mass conservation it need to be balanced as below

4 Al + 3 O₂ → 2 Al₂O₃

Al₂O₃ is the product, therefore the number of oxygen atom

= coefficient in front of Al₂O₃ * subscript of O

=2 x 3 = 6 atoms