Answer:
1.81 x 10²⁴ atoms He
Explanation:
You can find the amount of atoms by multiplying the given moles by Avogadro's Number. This number represents the amount of atoms per 1 mole. It is important to arrange the ratio in a way that allows for the cancellation of units.
Avogadro's Number:
6.022 x 10²³ atoms = 1 mole
3 moles He 6.022 x 10²³ atoms
-------------------- x -------------------------------- = 1.81 x 10²⁴ atoms He
1 mole