Calcium phosphate, Ca3(PO4)2, has a formula mass of 310.18 amu. What is the mass of 0.500 mol of calcium phosphate?

1. A formula mass of 310.18 amu means a molar mass of 310.18 g/mol, since the two are numerically equal. 2. Mass equals moles multiplied by molar mass. 3. Substituting gives 0.500 mol x 310.18 g/mol = 155.1 g. 4. Units check: mol x g/mol leaves grams. 5. The value 310.2 g ignores that only half a mole is present, and 620.4 g divides by 0.500 instead of multiplying. _Source: OpenStax Chemistry (CC BY 4.0), Ch 3 "Composition of Substances and Solutions", section 3.1 Formula Mass and the Mole Concept_