What units are used to measure gas pressure?

2 Answers
May 20, 2018

Answer:

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

Answer:

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.#