a) how many moles of atoms are in 1 mole of Ca3(PO3)2

b)If I have 1 mole of Ca3(PO3)2, how many moles of PO3^3- ions do I have?
c)How many individual PO3^3- ions do I have?

4 answers

You use the subscripts to tell you.I will assume you made a typo and you meant to type in Ca3(PO4)2 but the instructions are the same for Ca3(PO3)2.
If you have 1 mol Ca3(PO4)2 you have 6.02E23 molecules of Ca3(PO4)2.
You have 3 mols of Ca ions, 2 of P, 12 of O and 3 of PO4^3-.
It wasn't a typo. It is (PO3)2
So you are saying it should be
a) 11 moles of atoms
b) 1 mole of PO3^3- ions
c) 2 ions of PO3^3- ions (because of the subscript 2 that follows (PO3)2)
Almost.
a. Yes, 11 mols of atoms (3 Ca, 2P, 6O = 11 total)
b. You have 2 mols PO3^2- (that subscript of 2 after the closed parentheses says 2.
c. I think c is asking for individual PO3^3-, which I missed the first time around. That means you have 6.02E23 ions in 1 mol so twice that for two mols.
Nice Gary