Why do chemists use a mercury column to measure pressure?

1 Answer
Apr 1, 2017

Good question.............


It turns out that atmospheric pressure, i.e. #1*atm# will support a column of mercury #760*mm# high. For an example of how this is used in a problem see here.

And thus a measurement of length can lead to a good determination of the pressure. If you isolate the mercury column from dynamic vacuum, you can see if your line has a pinhole leak if the mercury column drops. Chemists often use mercury barometers as a visual measurement of pressure.