The average speed of methane molecules (CH₄, molecular mass = 2.66 × 10^-26 kg) in the atmosphere of Neptune (temperature = 63 K = -210°C) is: A)313 m/s. B)327,000 m/s. C)572 m/s. D)98,000 m/s.

Question

Quizplus · Accepted Answer

The average speed of gas molecules can be calculated using the formula for the root mean square speed, $v_{rms} = \sqrt{\frac{3kT}{m}}$, where $k$ is the Boltzmann constant ($1.38 \times 10^{-23} \, \text{J/K}$), $T$ is the temperature in Kelvin, and $m$ is the mass of one molecule of the gas. Substituting the given values for methane ($m = 2.66 \times 10^{-26} \, \text{kg}$, $T = 63 \, \text{K}$), we find that the average speed is closest to 313 m/s, making option A correct.

The Average Speed of Methane Molecules (CH4, Molecular Mass =

The Average Speed of Methane Molecules (CH₄, Molecular Mass =