# Problem: Consider the following gases, all at STP: Ne, SF6, N2, CH4.Which one has the highest root-mean-square molecular speed at a given temperature?

###### FREE Expert Solution

root mean square speed (μrms)

$\overline{){\mathbf{\mu }}_{\mathbf{rms}}\mathbf{=}\sqrt{\frac{\mathbf{3}\mathbf{RT}}{\mathbf{M}}}}$

µrms = rms speed,
R = 8.314 J/(mol·K)
T = temperature, K
M = molar mass, kg/mol

Based on the equation for μrms, 3 and R are constants. All of the gases are at the same temperature (STP). The only difference the gases have is their molar masses (M).

###### Problem Details

Consider the following gases, all at STP: Ne, SF6, N2, CH4.

Which one has the highest root-mean-square molecular speed at a given temperature?

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Root Mean Square Speed concept. You can view video lessons to learn Root Mean Square Speed. Or if you need more Root Mean Square Speed practice, you can also practice Root Mean Square Speed practice problems.