Charles Law
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Charles law | V/T = const at fixed p | Charles & Gay-Lussac |
| Absolute scale | Temperature must be in kelvin | Kelvin scale |
| Expansion coefficient | α = 1/273.15 K⁻¹ ideal | Thermal expansion |
| Isobaric | Constant pressure and amount | Ideal gas law |
| Validity | Valid away from liquefaction | Equation of state |
| Conversion | T(K) = t(°C) + 273.15 | Scale conversion |
Constants used on this page and their authoritative sources, for verification and citation
| Constant | Value | Unit | Source |
|---|---|---|---|
| Celsius scale zero point T_0 | 273.15 | K | SI / ITS-90 defining value (exact) |
| Boiling point of water (1 atm) | 373.15 | K | ITS-90 (100 ℃ at 1 atm = 101325 Pa) |
| Standard atmosphere | 101 325 | Pa | ISO 2533 defining value (exact) |
Note: Charles's law requires absolute temperature; the isobaric volume ratio from 0 ℃ to 100 ℃ is 373.15/273.15 = 1.3661, i.e. an increase of about 36.61%.