when mercury ii oxide heated it decomposes mercury and oxygen gas according following balanc

When mercury (II) oxide is heated it decomposes into mercury and oxygen gas according to the following BALANCED equation. 2 HgO à 2 Hg + O2 Given that the density of oxygen is 1.439 g/L, how many liters of oxygen gas can be produced if 1.0 moles of mercury (II) oxide are heated?