Task:
How many grams would 3.37 x 10 22 atoms of sulfur be?
Solution:
According to Avogadro Law: 1 mol of substance contains 6.02⋅1023 atoms (molecules, ions).
n(mol)=N/NA
n – the amount of sulfur (mol)
N – the quantity of atoms of sulfur
NA – Avogadro constant (6.02⋅1023)
n(mol)=m(g)/MW(g/mol)m(g)/MW(g/mol)=N/NA
MW(S) = 32 g / mol (from the periodic table of elements)
The mass of sulfur is
m(S)=N⋅MW/NA=3.37⋅1022⋅32/(6.02⋅1023)=1.79 g
Answer: m(S)=1.79 g