How many molecules are in 0.2 mol of a gas? (Avogadro's number = 6.0 x 10^23)
Answer and explanation
Correct answer: C. 1.2 x 10^23
- Step 1: Number = moles x Avogadro's number. Step 2. = 0.2 x 6.0 x 10^23 = 1.2 x 10^23. Answer: 1.2 x 10^23. Why not the others: 1.2 x 10^24: That is out by a factor of ten. 3.0 x 10^24: That divides instead of multiplying. 6.0 x 10^22: That is a tenth of the correct number.
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