Engineering Board Exam Reviewer · Physics · hard
What is the rms speed of oxygen molecules (M = 32 g/mol) at 300 K? (R = 8.314 J/mol· K)
- 15.29 m/s
- 279.2 m/s
- 394.8 m/s
- 483.6 m/s
Answer
D. 483.6 m/s
Solution
vrms = sqrt(3RT/M) = sqrt(3 × 8.314 × 300/0.032) = 483.6 m/s.
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