1. What is Partial Pressure by Henry Solubility?

Definition: This calculator determines the partial pressure of a gas species based on its concentration in aqueous phase and Henry's solubility constant.

Purpose: It helps in understanding gas-liquid equilibrium systems, particularly in environmental engineering, chemical processes, and atmospheric studies.

2. How Does the Calculator Work?

The calculator uses Henry's Law formula:

Where:

• \( P_{species} \) — Partial pressure of the species in gas phase (Pa)
• \( c_a \) — Concentration of species in aqueous phase (mol/m³)
• \( H_{cp} \) — Henry's solubility constant (mol/(m³·Pa))

Explanation: The concentration in aqueous phase is divided by Henry's constant to determine the equilibrium partial pressure in the gas phase.

3. Importance of Partial Pressure Calculation

Details: Understanding partial pressures is crucial for gas absorption/desorption processes, environmental fate modeling, and industrial gas treatment systems.

4. Using the Calculator

Tips: Enter the aqueous concentration (mol/m³) and Henry's constant (mol/(m³·Pa)). Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is Henry's Law?
A: Henry's Law states that the amount of dissolved gas is proportional to its partial pressure in the gas phase at equilibrium.

Q2: Where can I find Henry's constants?
A: Henry's constants are typically found in chemical engineering handbooks or thermodynamic databases for specific gas-water systems.

Q3: Does temperature affect Henry's constant?
A: Yes, Henry's constant is temperature-dependent, generally decreasing with increasing temperature for most gases.

Q4: What units should I use?
A: This calculator uses SI units: concentration in mol/m³, Henry's constant in mol/(m³·Pa), resulting in pressure in Pascals.

Q5: Can this be used for gas mixtures?
A: Yes, for each component in the mixture, provided you use the appropriate Henry's constant for each species.