Acompound contains 14.5 g of magnesium and 3.5 g of oxygen. what is the mass percent of oxygen in the compound?

im not completely sure if this is correct, but this is what I did. and how I got my answer.

(3.5 g) / (14.5 + 3.5) g = 0.19 = 19% O by mass

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.

a corroding iron, if that's one of your choices