What is the mass in grams of oxygen which contains 1.5 × 10²² molecules?
Correct answer: B. 0.80 g
- A. 0.08 g
- B. 0.80 g
- C. 8.0 g
- D. 80 g
Explanation
First, find the moles of O₂: (1.5 × 10²²) / (6.022 × 10²³) ≈ 0.025 mol. Then, calculate the mass: 0.025 mol × 32 g/mol (for O₂) = 0.8 g.
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