Question

calculate
a) the mass of one atom of chlorine
b) the mass of one molecule of chlorine
c) the mass of one mole of chlorine gas

Answer 1

1 mole = 6.023 ×10^23 atoms
molecular weight of chlorine = 35.5 gm
1 mole has a mass of 35.5 gm of Chlorine
so, 
a) mass of one atom = 35.5/(6.023 ×10^23) = 5.89 × 10^(-23) gm
b) mass of one molecule = 2× mass of one atom
                                         =2× 5.89 × 10^(-23)
                                         =11.78  × 10^(-23) gm
c) mass of one mole = molecular weight = 35.5 gm