I know the answer, I just don't know how my teacher got it. Can anyone teach me how to solve it please. How many moles of oxygen are present in 0.798 moles of Mg(IO3)2?
4.79 mol

About 4.79 moles of oxygen.

Explanation:

We want to determine the amount of moles of oxygen are present in 0.798 moles of Mg(IO₃)₂.

From the chemical formula, we can see that there are six atoms of oxygen for every molecule of Mg(IO₃)₂. Therefore, we can say that there are six moles of oxygen for every mole of Mg(IO₃)₂. This yields the following ratio:

Multiplying this by the initial value yields:

In conclusion, there are about 4.79 moles of oxygen present in 0.798 moles of Mg(IO₃)₂.