How many formula units of magnesium oxide will form when excess magnesium reacts with 480 molecules of oxygen?

The balanced chemical equation for the reaction of magnesium with oxygen is:

2Mg + O2 → 2MgO

From this equation, we can see that one molecule of oxygen (O2) reacts with two atoms of magnesium (Mg) to form two formula units of magnesium oxide (MgO). Therefore, the ratio of O2 to MgO is 1:2.

Given that we have 480 molecules of oxygen, we can use this ratio to find the number of formula units of magnesium oxide that will form:

480 O2 * 2 MgO/O2 = 960 MgO

So, 960 formula units of magnesium oxide will form when excess magnesium reacts with 480 molecules of oxygen.