How do you answer this chemistry question?

Question

How many atoms of mercury are present in

3.4 cubic centimeters of liquid mercury?

The density of mercury is 13.55 g/cc.

Answer in units of atoms.

Answer 1

Avogadro's number is 6.023 x 10^23 atoms per atomic mass in grams (mole).  Multiply 3.4cc x 13.55g/cc to get the total grams.  Divide that by mercury's atomic weight to give the number of moles.  Multiply that answer by Avogadro's number to get the number of atoms.