Move the gas pressure and the room pressure and watch the mercury answer. The same push appears in six units at once, so you can see how atm, torr, kPa and the rest line up.
Slide the gas pressure and watch the mercury shift.
Every unit here is tied to the same anchor: 1 atm = 760 torr = 101.325 kPa = 1.01325 bar = 14.696 psi.
| Unit | Gas pressure |
|---|---|
| atm | |
| torr | |
| mmHg | |
| kPa | |
| bar | |
| psi |
torr and mmHg are the same size, because one torr was defined as the push of a column of mercury one millimeter tall.