Please help If You Are Able To. Where do these go?

Tin has ten stable isotopes. the heaviest, 124sn, makes up 5.80% of naturally occuring tin atoms. how many atoms of 124sn are present in 82.0 g of naturally occurring tin? what is the total mass of the 124sn atoms in this sample?

I’m an electrically neutral atomic any element, there are equal numbers of

Which substance can be broken down by chemical means