1. What is Equilibrium Vapour Density?

Definition: Equilibrium Vapour Density is the density of a vapour substance during the stages of reaction at equilibrium.

Purpose: It helps chemists and chemical engineers understand the state of a chemical reaction at equilibrium and predict product formation.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( d \) — Equilibrium Vapour Density
• \( M \) — Total Moles at Equilibrium
• \( \alpha \) — Degree of Dissociation (0 to 1)
• \( N_{moles} \) — Number of Moles
• \( V \) — Volume of Solution (m³)

Explanation: The formula accounts for the dissociation of molecules and the resulting change in total number of particles in the system.

3. Importance of Vapour Density Calculation

Details: Calculating vapour density at equilibrium helps determine the extent of reaction, predict product yields, and understand reaction thermodynamics.

4. Using the Calculator

Tips: Enter the total moles at equilibrium, degree of dissociation (default 0.35), number of moles (default 2), and volume of solution in m³ (default 0.45).

5. Frequently Asked Questions (FAQ)

Q1: What is degree of dissociation?
A: Degree of dissociation (α) represents the fraction of molecules that dissociate into smaller particles (0 = no dissociation, 1 = complete dissociation).

Q2: How does number of moles affect the calculation?
A: Number of moles (N) represents how many moles the original compound breaks into. For example, PCl₅ → PCl₃ + Cl₂ has N=2.

Q3: What units should I use for volume?
A: The calculator uses cubic meters (m³). For liters, divide by 1000 (1 m³ = 1000 L).

Q4: Can I use this for any chemical reaction?
A: This applies to gas-phase reactions where the degree of dissociation is known and the ideal gas law applies.

Q5: What if my degree of dissociation is unknown?
A: You'll need experimental data or equilibrium constants to estimate the degree of dissociation first.