To answer this question,
we want to use Avogadro's number to convert atoms to moles,
then we'll use molecular weight to convert moles to grams

4.2 x 10²⁴ atoms S

(1 mole S) / (6.022 x 10²³ atoms S)

(32.06 g S) / (1 mole S)

= 223.59 g S

4.2 x 10²⁴ atoms of sulfur = 2.2 x 10² g S