Question

Convert 25.4 grams of barium phosphate, Ba3(PO4)2 to formula units.

Answer 1

To solve this questions you first need to find the number of moles of barium phosphate you have. The molar mass of barium phosphate is 601.93g/mol.
24.4/601.83 = 0.0402 moles barium phosphate
Then you need to use avagadro’s number, 6.022 x 10^23, which is the number of molecules or formula units in a mole.

6.022 x 10^23 * 0.0402 = 2.42 x 10^22 formula units