Convert 0.20 mol of boron into grams of boron. how many atoms are present?

Explanation:

As molar mass of boron is 10.8 g/mol and it is given that its number of moles is 0.20 mol.  

Therefore, calculate its mass as follows.

              No. of moles =

                    0.20 mol =

                                    = 2.16 g

And, according to the mole concept there are present in 1 mole of a substance.

Mathematically,    1 mole = atoms or molecules

Therefore, calculate the number of atoms present in 0.20 mol of boron as follows.

                 = atoms

Thus, we can conclude that mass of boron is 2.16 g and it contains atoms.