Answer
4.94x10^22 molecules
explanation
to calculate the number of molecules in 8.21x10^-2 moles ca be determined by using Avogadros number
we know that
1 mol has 6.022x10^23 molecules
therefore,
8.21x10^-2 moles have:
(8.21x10^-2) x (6.022x10^23)
= 4.94x10^22 molecules
