Final answer:
To find the number of entities in each sample, you can use Avogadro's number. For example, in 3.21 mol of argon atoms, there are approximately 1.93 × 10^24 argon atoms.
Step-by-step explanation:
In order to determine the number of entities in each of the given samples, we use Avogadro's number, which is approximately 6.022 × 10^23 entities per mole.
a. 3.21 mol of argon atoms:
Number of argon atoms = 3.21 mol × (6.022 × 10^23 atoms/mol) = 1.93 × 10^24 argon atoms
b. 1.3 × 10⁻¹² mol of marbles:
Number of marbles = 1.3 × 10⁻¹² mol × (6.022 × 10^23 marbles/mol) = 7.82 × 10^11 marbles
c. 3 × 10⁶ mol of water molecules:
Number of water molecules = 3 × 10⁶ mol × (6.022 × 10^23 molecules/mol) = 1.8066 × 10^30 water molecules
d. 7.63 × 10⁻¹⁸ mol of basketballs:
Number of basketballs = 7.63 × 10⁻¹⁸ mol × (6.022 × 10^23 basketballs/mol) = 4.60 × 10^6 basketballs