Molar mass of phosphoric acid
97.99 g/molH₃PO₄
Molar mass
Molar mass. The mass of one mole in grams: add the atomic mass of every atom in the formula. Masses. Standard atomic masses to two decimals, hydrogen 1.008, every element to uranium. Typing. Ca(OH)2, (NH4)2SO4, CuSO4.5H2O and K4[Fe(CN)6] all work.
97.99g/mol
H₃PO₄
- H× 33.09%
- P× 131.60%
- O× 465.31%
- H3 × 1.0083.024
- P1 × 30.9730.97
- O4 × 16.0064.00
- Total97.99 g/mol
Grams, moles, particles
Type any one. The other three fill in. Moles. From grams, particles or litres they are rounded to 3 significant figures first, as in a worked answer. 1 mol = 6.022 × 10²³ particles = 22.7 L of gas at STP (1 bar); 22.4 L at 1 atm.
1 mol of H₃PO₄ = 6.022 × 10²³ molecules
At 1 atm (older value): 22.40 L
Add up the atoms
- Hydrogen: 3 × 1.008 = 3.024 g
- Phosphorus: 1 × 30.97 = 30.97 g
- Oxygen: 4 × 16.00 = 64.00 g
- Molar mass = 3 × 1.008 + 30.97 + 4 × 16.00 = 97.99 g/mol
Share of the mass
- Hydrogen3.09%
- Phosphorus31.60%
- Oxygen65.31%
1 mol of H₃PO₄ = 97.99 g
1 g of H₃PO₄ = 0.01020 mol
Molar mass of phosphoric acid: quick answers
What is the molar mass of phosphoric acid?
The molar mass of phosphoric acid, H₃PO₄, is 97.99 g/mol. So 1 mol of phosphoric acid has a mass of 97.99 g.
How do you calculate the molar mass of H₃PO₄?
Add the atomic masses of all the atoms: 3 × 1.008 + 30.97 + 4 × 16.00 = 97.99 g/mol.
What is the percentage of oxygen in phosphoric acid?
Oxygen is 65.31% of the mass of H₃PO₄: 64.00 g in every 97.99 g. In full: H 3.09%, P 31.60%, O 65.31%.