2.4 g of magnesium reacts with 1.6 g of oxygen. What is the empirical formula of the oxide formed?

Ar of Magnesium = 24; Ar of Oxygen = 16

number of moles = mass divided by Ar

number of moles of Mg = 2.4/24 = 0.1

number of moles of Oxgen = 1.6/16 = 0.1

ratio of Mg to O = 0.1:0.1 = 1:1 So oxide produced is MgO