An iron oxide is 77.7% in iron. Its empirical formula is ________.

Question

Quizplus · Accepted Answer

The empirical formula represents the simplest whole-number ratio of atoms in a compound. Since iron oxide is 77.7% iron, we can assume that the remaining 22.3% is oxygen. To get the simplest whole-number ratio, we divide both the iron and the oxygen percentages by their respective atomic weights (56 for iron and 16 for oxygen). This gives us a ratio of 1 iron to 1 oxygen or FeO. Therefore, the empirical formula of iron oxide is FeO.

An Iron Oxide Is 77