Partial Pressure Calculator

Partial Pressure Calculator

The Partial Pressure Calculator computes the partial pressure of a gas in a mixture using Dalton's law, the ideal gas law, or Henry's law. Partial pressure is the pressure a single gas component would exert if it alone occupied the container.

Dalton's law states that total pressure equals the sum of partial pressures:

$$P_{\mathrm{total}} = p_1 + p_2 + \cdots + p_n$$

For a component with mole fraction $x_i$, the partial pressure is $p_i = P_{\mathrm{total}} \times x_i$.

From the ideal gas law, $p_i = n_i R T / V$, where $n_i$ is moles of the gas, $R = 0.082057$ L·atm/(mol·K), $T$ is temperature in kelvin, and $V$ is volume in liters.

Henry's law relates dissolved gas concentration to partial pressure: $P = K_H \times C$ for concentration in mol/L, or $P = K_{H2} \times x$ for mole fraction.

Related tools: Mole Fraction Calculator, Kp Calculator, and Ideal Gas Law Calculator.