How many carbon dioxide molecules are present in 0.25 mol of CO₂? (Avogadro constant = 6.02 × 10²³ per mol)
Answer and explanation
Correct answer: D. 1.505 × 10²³
- Step 1: Number of particles = moles × Avogadro constant. Step 2. 0.25 × 6.02 × 10²³ = 1.505 × 10²³. Answer: 1.505 × 10²³. Why not the others: 0.042 × 10²³ is what you get if you divide by Avogadro's constant. 1.505 × 10²² is what you get if you misplace a power of ten. 1.505 × 10²⁴ is what you get if you misplace a power of ten.
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