If I have #9.71xx10^22# #"platimum atoms"#, what molar quantity, and what mass of metal are present?
You have approx
So you should have a mass of approx.
I appreciate that it is hard to work with such unfeasibly large numbers. But remember that the mole is just another number, like a score, or a dozen, or 1 gross - it's just that a mole is *&&??! LARGE.
This idea of molar and mass equivalence is something that is fundamental to chemistry, and you should take some effort to appreciate it.