Need asap! 25 pts! magnetic iron oxide has 72.4% iron and 27.6% oxygen. what is the empirical formula?

Hi!

1. Assume that these percentages are the mass.

2. For each of Fe and O, divide the mass by the Ar (relative atomic mass).

Fe: 72.4/55.8 = 1.297 moles

O: 27.6/16 = 1.725 moles

3. Work out which mole value is smallest, then divide the bigger mole value by the smaller one.

1.297 is smaller than 1.725, so your empirical formula is 1.1297/1.1297 = 1 atom of iron, and 1.725/1.297 = 1.33 atoms of oxygen.

4. Ensure your atom values are whole numbers.

1.33 is not a whole number, so multiply both 1 and 1.33 by 3.

5. Write out your empirical formula.

Fe3O4

Hope that helps!

nacl or sodium chloride is an ionic compound. this is because an ionic compound pertains to a compound that consists of positively and negatively charged ions. in this case, na (sodium) has a tendency to lose one electron when it reacts with with other atoms, so the resulting sodium ion contains 11 protons and 10 electrons, thus making it positively charged (na+), when chlorine reacts, it usually gains one electron to form an ion called chloride, thus making it negatively charged ( since the ions are oppositely charged, they attract.