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Calculate the value of mean free path (λ) for oxygen molecules at temperature 27°C and pressure 1.01 × 10⁵ Pa. Assume the gas molecular diameter is 0.3 nm and the gas is ideal. (k = 1.38 × 10⁻²³ J K⁻¹)
- 58 nm
- 32 nm
- 86 nm
- 102 nm
Correct answer: 102 nm
Solution
The mean free path (λ) is calculated using the formula λ = kT / (√2πd²P), where k is the Boltzmann constant, T is the temperature in Kelvin, d is the molecular diameter, and P is the pressure. Substituting the given values results in a mean free path of 102 nm, confirming that option D is correct.
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