How much oxygen is needed to react with 6.4 g of sulfur (IV) oxide SO2 to form sulfur (VI) oxide?

1.Calculate the amount of sulfur oxide (IV) substance according to the formula:

n = m: M, where M is molar mass.

M (SO2) = 32+ 32 = 64 g / mol.

n = 6.4: 64 g / mol = 0.1 mol.

2. Let us compose the reaction equation for the combustion of sulfur oxide:

2SO2 + O2 = 2SO3.

According to the reaction equation, there is 1 mole of oxygen per 2 mol of sulfur (IV) oxide, that is, the substances are in quantitative ratios of 2: 1, the amount of oxygen substance will be 2 times less than the amount of SO2.

2n (SO2) = n (O2) = 0.1 × 2 = 0.2 mol.

3.Find the volume of oxygen

V = Vn n, where Vn is the molar volume of gas, equal to 22.4 l / mol, and n is the amount of substance.

V = 22.4 L / mol × 0.2 mol = 4.48 L.

Answer: V = 4.48 liters.