The mass of 3.91 x10^24 sulfur atom is calculated as follows
find the number moles of sulfur
by use of Avogadro constant that is 1 mole = 6.02 x10 ^23 atom
what about 3.91 x10^24 atom
(3.91 x10^ 24) / (6.02 x10^23) = 6.495 moles
mass= moles x molar mass
= 6.495 mole x 32 g/mol = 207.84 grams
