Question

What is the mass, in grams, of a sample of 1.20 × 1022 atoms of mercury (Hg)? Show your work or explain the steps that you used to determine your answer.

Answer 1

m=n*Mr

Answer 2

Divide by Avogadro's number (6.002*10^23), you now have the amount of moles Hg.
Next you multiply by the molecular weight of mercury (you can find it in a periodic table: http://ptable.com )
Now you have the mass in grams.