Total Pressure for Binary Vapour System for Dew-Bubble Point Calculations with Raoult's Law Calculator

Total Pressure Formula:

\[ P_T = \frac{1}{\left(\frac{y_1}{P_{1}^{sat}} + \frac{y_2}{P_{2}^{sat}}\right)} \]

Mole Fraction of Component 1 in Vapour Phase (y₁):

Saturated Pressure of Component 1 (P₁^sat):

Mole Fraction of Component 2 in Vapour Phase (y₂):

Saturated Pressure of Component 2 (P₂^sat):

Total Pressure of Gas (P_T):

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1. What is Total Pressure for Binary Vapour System?

Definition: This calculator computes the total pressure of a binary vapour system using Raoult's Law for dew-bubble point calculations.

Purpose: It helps chemical engineers and researchers determine the equilibrium pressure of a two-component vapour system.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ P_T = \frac{1}{\left(\frac{y_1}{P_{1}^{sat}} + \frac{y_2}{P_{2}^{sat}}\right)} \]

Where:

\( P_T \) — Total pressure of gas (Pa)
\( y_1 \) — Mole fraction of component 1 in vapour phase
\( P_{1}^{sat} \) — Saturated pressure of component 1 (Pa)
\( y_2 \) — Mole fraction of component 2 in vapour phase
\( P_{2}^{sat} \) — Saturated pressure of component 2 (Pa)

Explanation: The formula calculates the total system pressure based on the composition of the vapour phase and the saturation pressures of the pure components.

3. Importance of Total Pressure Calculation

Details: Accurate pressure calculations are essential for designing distillation columns, vapor-liquid equilibrium studies, and process simulations.

4. Using the Calculator

Tips: Enter the mole fractions (must sum to ≤ 1) and saturation pressures for both components. All pressure values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is Raoult's Law?
A: Raoult's Law states that the partial pressure of a component in a mixture is equal to the product of its mole fraction in the liquid phase and its vapor pressure as a pure substance.

Q2: When is this calculation most accurate?
A: This calculation is most accurate for ideal mixtures where the components have similar molecular sizes and intermolecular forces.

Q3: What if my mole fractions don't sum to 1?
A: The calculator will still work, but the result assumes the remaining fraction is non-condensable gas or other components not accounted for.

Q4: How do I find saturation pressures?
A: Saturation pressures can be found in chemical engineering handbooks or calculated using Antoine equation for a given temperature.

Q5: Can this be used for non-ideal systems?
A: For non-ideal systems, activity coefficients should be included in the calculation (modified Raoult's Law).