The answer is 9.03 × 10²⁴ molecules of oxygen!
- Step 1 6.02 × 10²³ molecules : 1 mol = x : 15 mol
- Step 2 x = 6.02 × 10²³ molecules * 15 mol * 1 mol
- Step 3 x = 90.3 × 10²³ molecules
- Step 4 x = 9.03 × 10 × 10²³ molecules
- Step 5 x = 9.03 × 10²³⁺¹ molecules
- Step 6 { x = 9.03 × 10²⁴ molecules }