grams to moles to atoms
(41.6)g/(1 )×(1mol)/(87)g×(6.022×10^23)atoms/(1mol)
the 87 comes from the periodic table Sr has 87 as atomic weight
grams cancel then moles cancel and you are left with atoms
=2.87×10^23atoms
with all numbers it is 2.8794851×10^23atoms
