Kilopascals to mmHg Converter
Common Conversions
| kPa | mmHg |
|---|---|
| 0.133 | 1 |
| 1 | 7.501 |
| 5 | 37.503 |
| 10 | 75.006 |
| 13.332 | 100 |
| 25 | 187.52 |
| 50 | 375.03 |
| 100 | 750.06 |
| 101.325 | 760 |
| 200 | 1500.12 |
| 500 | 3750.31 |
Why this conversion matters in chemistry
Digital pressure gauges mostly read in kPa these days, but the vapor-pressure literature that feeds rotovap and freeze-drying protocols is full of mmHg values. 2.7 kPa on a Schlenk-line gauge is about 20 mmHg; 3.17 kPa is 23.8 mmHg — the vapor pressure of water at 25°C. Multiplying by 7.50062 does the conversion. The factor drops directly out of 101.325 kPa being 760 mmHg, so you can reconstruct it if you forget. The step comes up whenever a modern instrument reading has to match an older purification recipe or a tabulated vapor-pressure value.
Formula
Worked Examples
Sea-level atmospheric pressure — the defining anchor for both units.
1 bar — IUPAC standard pressure since 1982. Slightly below 1 atm, which is where the 760 versus 750 mmHg discrepancy between old and new conventions originates.
Water vapor pressure at 25°C. The correction applied when collecting a gas over water to get the dry-gas partial pressure.
A clean reference point. 100 mmHg is also the upper clinical threshold for diastolic blood pressure, so the number appears in several non-chemistry contexts too.