Determine the number of moles of each specified atom or ion in the given samples of the following compounds.( Hint: the formula tells you how many atoms or ions are in each molecule of formula unit.)

a. O atom in 3.161x10^21 molecules of CO2
b. C atom in 3.161x10^21 molecules of CO2

c. O atom in 2.2222x10^24 molecules of CO2
d. K^+ ions in 5.324 *10^16 formula units of KNO2
e. CL^ - ions in 1.000 x 1o^14 formula units of MgCl2
f. N atoms in 2.000 * 10^14 formula units of Ca (NO3)2
g. O atoms in 4.999 x 10^25 formula units of Mg3(PO4)2

5 answers

this is answered below
ok can you help with h instead.
h?? where
i mean g
You know from below how to determine moles of the compound, Mg3(PO4)2. Now how many O atoms are in the compound?