Ideal Gas Pressure
由理想气体状态方程求给定体积下的气体压强。
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Ideal gas law | pV = nRT | Clapeyron equation |
| Universal gas constant | R = 8.314462618 J/(mol·K) | CODATA 2018 |
| Amount of substance | n = m/M | Molar conversion |
| Specific gas constant | R_s = R/M, air 287 J/(kg·K) | Engineering thermodynamics |
| Absolute pressure | Use absolute, not gauge pressure | Pressure reference |
| Deviation | Use Z at high p / low T | Real gas correction |
Constants used on this page and their authoritative sources, for verification and citation
| Constant | Value | Unit | Source |
|---|---|---|---|
| Molar gas constant R = N_A·k | 8.314462618 | J·mol⁻¹·K⁻¹ | Derived from exact N_A and k (exact) |
| Avogadro constant N_A | 6.02214076 × 10²³ | mol⁻¹ | SI defining constant (exact) |
| Boltzmann constant k | 1.380649 × 10⁻²³ | J·K⁻¹ | SI defining constant (exact) |
| Molar volume of ideal gas (273.15 K, 101.325 kPa) | 22.41396954 | L·mol⁻¹ | Derived from R, T and p (V_m = RT/p) |
Note: R belongs to the revised SI set of exact defining constants; the ideal gas law holds only approximately at low pressure and high temperature, far from liquefaction.