Pressure rise in a vaccum system gas specific?

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Introducing a gas into a closed vacuum system at a constant rate, such as 10 SCCM, will result in a pressure rise that is dependent on the specific gas species. Different gases have varying molecular masses, which affects the pressure increase for the same volume introduced. Consequently, evacuating the system and introducing a different gas at the same flow rate will not guarantee an identical rate of pressure rise. This variation is due to differences in the average absolute momentum of gas particles across different species. Understanding these principles is crucial for accurately calibrating flow controllers.
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If I introduce a gas into closed vacuum system at a known rate let's say 10 SCCM there will be a subsequent pressure rise over time. Is that pressure rise gas species dependent. If I evacuate the system and introduce a different gas at 10 SCCM should I see the same rate of pressure rise?

Im trying to calibrate some flow controllers with respect to each other and I want to be sure my basic understanding is correct.

Thanks
 
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No, you will not necessarily see the same pressure rise. A given volume of a gas "A" does not necessarily cause the same increase in pressure as another volume of gas "B". This is because the average molecular mass of each gas species are different. This means that the average absolute momentum (ignoring vector direction) of the particles is different for a given volume and temperature across various species.
 

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