Mole Fraction Calculator Density Formula

Mole Fraction Formula:

\[ X_i = \frac{\rho_i \times V_i / MW_i}{\sum(\rho_j \times V_j / MW_j)} \]

Density (ρ):

g/mL

Volume (V):

Molecular Weight (MW):

g/mol

Sum of (ρ_j×V_j/MW_j):

dimensionless

Mole Fraction (X_i):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Mole Fraction?

The mole fraction (X_i) is a way of expressing the concentration of a component in a mixture. It is defined as the ratio of the number of moles of one component to the total number of moles of all components in the mixture.

2. How Does the Calculator Work?

The calculator uses the mole fraction formula:

\[ X_i = \frac{\rho_i \times V_i / MW_i}{\sum(\rho_j \times V_j / MW_j)} \]

Where:

\( X_i \) — Mole fraction of component i (dimensionless)
\( \rho_i \) — Density of component i (g/mL)
\( V_i \) — Volume of component i (mL)
\( MW_i \) — Molecular weight of component i (g/mol)
\( \sum(\rho_j \times V_j / MW_j) \) — Sum for all components in the mixture

Explanation: The numerator calculates the moles of component i, while the denominator sums the moles of all components in the mixture.

3. Importance of Mole Fraction

Details: Mole fraction is used in various chemical calculations including vapor-liquid equilibrium, colligative properties, and gas laws. It is temperature-independent and always sums to 1 for all components in a mixture.

4. Using the Calculator

Tips: Enter the density (g/mL), volume (mL), and molecular weight (g/mol) for your component, plus the sum of (ρ×V/MW) for all components. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why use mole fraction instead of other concentration measures?
A: Mole fraction is advantageous because it's temperature-independent and useful for gas mixtures and thermodynamic calculations.

Q2: What's the range of possible mole fraction values?
A: Mole fraction ranges from 0 (component absent) to 1 (pure component). The sum of all mole fractions in a mixture equals 1.

Q3: How do I get the denominator (sum) value?
A: Calculate (ρ×V/MW) for each component in your mixture and sum all these values.

Q4: Can I use this for gas mixtures?
A: Yes, but you'll need to use appropriate density values for gases at your conditions (temperature and pressure).

Q5: What if my mixture has more than two components?
A: The formula works for any number of components - just include all components in the denominator sum.