Raoult's Law Calculator
Calculate the vapor pressure of a solution containing a non-volatile solute.
Calculation Parameters
Adjust the values below.
Calculated Result
Expert Tip
Ensure units are correctly formatted (e.g. Kelvin for gas temperatures and liters for volumes) to get chemically accurate outputs.
How this Calculator Works
This calculator allows you to solve Raoult's Law problems dynamically. Adjust the input parameters using the sliders or selection menu below:
- Pure Solvent Vapor Pressure (kPa) (Range: 0.1 to 200.0, Default: 3.17)
- Solvent moles (n_solvent) (Range: 0.1 to 100.0, Default: 10.0)
- Solute moles (n_solute) (Range: 0.0 to 10.0, Default: 1.0)
The results are computed instantly and updated in the results panel on the right.
Formula & Methodology
where X_solvent = n_solvent / (n_solvent + n_solute)
Where:
- Pure Solvent Vapor Pressure: Parameter value.
- Solvent moles: Parameter value.
- Solute moles: Parameter value.
Step-by-Step Calculation Example
To calculate Raoult's Law manually, follow these steps:
- Identify the input parameters. For example:
- Pure Solvent Vapor Pressure (kPa) = 3.17
- Solvent moles (n_solvent) = 10.0
- Solute moles (n_solute) = 1.0
- Apply the formula:
P_solution = X_solvent * P°_solvent
where X_solvent = n_solvent / (n_solvent + n_solute) - Verify the calculated value which is updated instantly in the results panel on the right.
Frequently Asked Questions
What is Raoult's Law? ▼
P_solution = X_solvent × P°_solvent, where P_solution is solution vapor pressure, X_solvent is mole fraction, and P° is pure solvent vapor pressure.
What is vapor pressure lowering? ▼
Adding a non-volatile solute lowers the vapor pressure of the solvent proportionally to the mole fraction of solute added.
What defines an ideal solution? ▼
An ideal solution obeys Raoult's Law across all concentrations with zero heat of mixing and uniform intermolecular forces.