G x mol/g x atoms/mol=

what are the units remaining after conversion

The "unit" remaining after conversion is atoms.

This is a way to calculate the number of atoms, in an specific mass.

Explanation:

When you have a mass, multiplying the molar mass, "grams" are cancelled, so you finally obtained, number of moles.

Moles. atoms/mol, cancel the word mol so you will find out a number of atoms, present at the mass from, the begining.

For example, how many atoms are in 10 g of NaCl

Molar mass NaCl = Na mass + Cl mass

23 + 35.45 = 58.45 g/m

10 g. 1 / 58.45 mol/g. NA / 1 mol = 3.42x10²⁰ atoms

NA = Avogadro number