Simple RMS velocity question, what's wrong with my answer?

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The calculation for the root mean square (RMS) speed of an argon atom was initially performed using the ideal gas law and the formula for v_RMS. The user arrived at a speed of 12.5 m/s, but this was identified as incorrect. The error was attributed to a misplaced factor of 1000, likely due to the conversion from kPa to Pa. Correcting this factor is essential for obtaining the accurate RMS speed.
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Find the rms speed for an argon atom if 1.5 mol of the gas is confined to a 5.6 liter container at a pressure of 5.5 atm.

PV = nRT
RT = PV/n
v_RMS = \sqrt (3RT/M)

= \sqrt (3PV/nM)

= \sqrt ((3 * (5.5atm * 101.325kPA/atm) * (5.6 * 10^-3 m^3) / (1.5 mol * 39.948 * 10^-3)

= 12.5 m/s

However this is apparently wrong. Can someone please tell me what I went wrong?

Thanks
 
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Your substitutions are correct, but you've slipped a factor of 1000 (possibly the k in kPa) in your working out. This becomes a factor of sqrt (1000).
 
Thank you!
 

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