Calculate the mass of magnesium oxide that is obtained when 12 g of magnesium are burned.

The oxidation reaction of magnesium with oxygen is described by the following chemical reaction equation:

Mg + ½ O2 = MgO;

½ mole of gas is reacted with 1 mole of metal. 1 mole of its oxide is synthesized.

Let’s calculate the available chemical amount of magnesium.

M Mg = 24 grams / mol; N Mg = 12/24 = 0.5 mol;

Let’s calculate the weight of magnesium oxide.

M MgO = 24 + 16 = 40 grams / mol; m MgO = 40 x 0.5 = 20 grams;

Let’s calculate the weight of oxygen.

M O2 = 16 x 2 = 32 grams / mol; m O2 = 32 x 0.25 = 8 grams;

Let’s calculate the volume of oxygen. To do this, multiply the amount of substance and the standard volume of 1 mole of gaseous substance. 1 mole of ideal gas fills a volume of 22.4 liters under normal conditions.

V O2 = 0.25 x 22.4 = 5.6 liters;