Final answer:
To find how many helium atoms are in a 2.2 g helium balloon, we calculate the moles based on the atomic weight of helium and then use Avogadro's number to convert moles to atoms, resulting in 3.3 x 10^23 helium atoms.
Step-by-step explanation:
To determine how many helium atoms are in a balloon filled with 2.2 g of helium, we need to use the concept of moles and Avogadro's number. We start by calculating the number of moles of helium since the atomic weight of helium is approximately 4 g/mol. The calculation is as follows:
Number of moles = mass (g) / atomic weight (g/mol)
Number of moles = 2.2 g / 4 g/mol = 0.55 moles
To convert moles to atoms, we multiply the number of moles by Avogadro's number (6.02 x 1023 atoms/mole). Therefore, the number of atoms in 0.55 moles of helium is:
Number of atoms = 0.55 moles x 6.02 x 1023 atoms/mole
Number of atoms = 3.3 x 1023 atoms
So, the correct answer is:
c) 3.3 x 1023 helium atoms