Answer: 1.90x10²³ atoms of O
Explanation: First convert the mass of O into moles:
5.06 g O x 1 mole O / 16 g O
= 0.32 moles O
Next use Avogadro's Number to find the number of atoms of O
0.32 moles O x 6.022x10²³ atoms O / 1 mole O
= 1.90x10²³ atoms O
