# Calculate the volume of phosphoric acid containing oxygen

## How do we calculate the volume of phosphoric acid that contains 7.85 x 10^{4} mg of oxygen?

What is the density of phosphoric acid and how do we convert the mass of oxygen from milligrams to grams?

## Volume of Phosphoric Acid Containing Oxygen

To calculate the volume of phosphoric acid that contains 7.85 x 10^{4} mg of oxygen, we need to first convert the mass of oxygen from milligrams to grams.

Given: Mass of Oxygen = 7.85 x 10^{4} mg

The density of phosphoric acid is 1.88 g/cm^{3}.

To convert the mass of oxygen from milligrams to grams, we use the conversion factor: 1 g = 1000 mg. Therefore, 7.85 x 10^{4} mg of oxygen is equal to 78.5 g of oxygen.

Next, we need to calculate the mass of phosphoric acid containing 7.85 x 10^{4} mg of oxygen. The molecular formula of phosphoric acid is H_{3}PO_{4}, which consists of 1 P atom, 4 O atoms, and 3 H atoms.

The molar mass of P is approximately 31 g/mol, O is approximately 16 g/mol, and H is approximately 1 g/mol. Therefore, the molar mass of H_{3}PO_{4} is about 98 g/mol.

Since phosphoric acid contains 4 moles of oxygen atoms, the mass of oxygen in one mole of H_{3}PO_{4} is 64 g.

Therefore, 78.5 g of oxygen is present in (78.5/64) * 98 = 120.39 g of phosphoric acid.

Using the density of phosphoric acid, we can calculate the volume in cm^{3} using the formula: Volume = Mass / Density.

Volume = 120.39 g / 1.88 g/cm^{3} = 64.03 cm^{3}.