N the balanced equation 4Fe + 3O2à 2Fe2O3, how many atoms of iron (Fe) are reacting with every three molecules of oxygen (O2) ?

Answer is: four iron atoms are reacting with every three molecules of oxygen.

Balanced chemical reaction: 4Fe + 3O ₂ → 2Fe₂O₃.

From chemical reaction: n (Fe) : n (O₂) = 4 : 3.

Ratios of atoms of iron and molecules of oxygen is 4 : 3 ...

There is four atoms of iron and six atoms of oxygen on both side of reaction.