What units are used to measure gas pressure?

2 Answers
May 20, 2018

A torr.

Explanation:

760 Torr equal one atm, or atmospheric pressure. And the piece of equipment used to measure torrs is manometer.

( Sorry this is short if you need further understanding await the answer of someone else. )

May 20, 2018

Perhaps we should finally address this question....

Explanation:

Gas pressure may be quoted with units of "foot-pounds", "mm Hg", "Pascals"...all of these report "force per unit area". For chemists, probably the most intuitive unit is the "atmosphere".

And "1 atmosphere"-=760*mm*Hg-=101.3*kPa-=32*"psi"...

As a refinement....engineers often speak of gauge pressure versus absolute pressure. When we fill a tyre on a car, and we use the manual in the car to give us the appropriate pressure, the "gauge pressure" is specified, the which is the pressure OVER atmospheric....i.e.

"gauge pressure"-="internal pressure "-" atmospheric pressure"

A tyre at atmospheric pressure would thus have "ZERO gauge pressure". Sometimes (especially in the States) we see "psig", i.e. "pounds per square inch gauge".

Thus "ZERO gauge pressure"=1*atm.