Themes > Science > Chemistry > Inorganic Chemistry > Gas Laws > The Basics > Units of Pressure


Torricelli determined that the standard atmospheric pressure was 760 mm Hg or 760 torr (named for Torricelli). Also 760 mm Hg is equal to 1 atm (standard atmospheric pressure)

1 atm = 760 mm Hg = 760 torr

Pressure is defined as force / area. In the metric system there is another unit for pressure and it is the pasca (Pa). There are 101325 Pa is every atm, so:

1 atm = 760 torr = 760 mm Hg = 101325 Pa


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