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Molar Mass of Na3PO4

Sodium Phosphate — 163.940 g/mol.

The molar mass of Na3PO4 (sodium phosphate) is 163.940 g/mol. A cleaning agent and food additive, strongly basic in solution.

M(Na3PO4) = (3 × 22.99) + (1 × 30.97) + (4 × 16) = 163.940 g/mol

Working

ElementAtomsAtomic massSubtotal% by mass
Na322.9968.970042.07%
P130.9730.974018.89%
O41663.996039.04%
Total163.9400100%

How this is calculated

Count the atoms of each element in the formula, multiply each count by that element's standard atomic weight, and add the results. The answer is in grams per mole: the mass of 6.022 × 1023 formula units.

Percent composition

Each element's share is its subtotal divided by the total, times 100. This is what empirical-formula questions run in reverse — given the percentages, recover the ratio of atoms.

Work out any other formula with the molar mass calculator, which handles brackets and hydrates. Atomic weights are IUPAC standard values, the same table the calculator uses.