a. Calculate the number of atoms in 1.22 10⁶ moles of helium.

a1. Calculate the number of moles of helium that contains 1.95 10²¹ atoms.

b. How many atoms are in 3.90 moles of selenium (Se)?

c. What is the mass in grams of 4.50 10¹² tin atoms?

d. The number of atoms in 6.91 moles of potassium

e. The number of moles of potassium that contains 8.91 10²⁵ atoms