Answer:
5.57 x 10^24 atoms
Step-by-step explanation:
first, you are seeking the number of ATOMS of Boron.
Boron has an Atomic mass of 10.8 g/mol (see #5 on the periodic table)
100 gm of Boron would have 100 g /10.8 g/mol =9.26 moles
each mole has Avogadros number of atoms 6.02 x 10^23
9.26 moles has 9.26 x 6.02 x 10^23 atoms =5.57 x 10^24 atoms