Pfeiffer Vacuum

1.2.3 Molecular number density

As can be seen from Formula 1-4 and Formula 1-5 pressure is proportional to molecular number density. Due to the high number of molecules per unit of volume at standard conditions, it follows that at a pressure of 10-12 mbar, for example, 26,500 molecules per cm3 will still be present. This is why it is not possible to speak of a void, or nothingness, even under ultra high vacuum.

Page functions
  • How would you rate this page?


  • Recommend this page!


  • Social Networks:


Contact options

Our points of contact are available to you at any time:

Display contact options


You can use our contact form to send your request or concern directly to us.

Contact Form

Headquarters postal address

Pfeiffer Vacuum GmbH
Berliner Strasse 43
35614 Asslar

P.O. Box

Pfeiffer Vacuum GmbH
Postfach 1280
35608 Asslar

T +49 6441 802-0
F +49 6441 802-1202

Copyright © 2015 Pfeiffer Vacuum GmbH