What is the pressure in atmospheres, if the pressure is reported to be #854*mm*Hg#?

1 Answer
Apr 6, 2017

Answer:

I do not know why we seem to be getting a lot of questions that quote pressures of #>760*mm*Hg............#

Explanation:

One atmosphere of pressure will support of column of mercury that is #760*mm# high. And thus we can use a colume on mercury to measure pressures that ARE LESS than #1*atm#, i.e #<760*mm*Hg#.

Given your problem, I suppose we could state that #854*"Torr"-=(854*"mm Hg")/(760 *"mm Hg"*atm^-1)=1.12*atm#. I really find the use of these units objectionable, because if you get a mercury spill in the lab, you have a major clean-up job, and guess who is going to do it?

And thus your question has not been consistently proposed. The pressure is LOWER at #1.12*atm#; i.e. it is expanded not compressed. Would you review this problem?