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Specific Latent Heat using Trouton's Rule Calculator

Specific Latent Heat Formula:

\[ L = \frac{bp \times 10.5 \times [R]}{MW} \]

K
kg

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1. What is Specific Latent Heat using Trouton's Rule?

Definition: This calculator estimates the specific latent heat of vaporization using Trouton's rule, which relates the boiling point and molecular weight of a substance.

Purpose: It helps chemists and engineers quickly estimate the energy required for phase changes without detailed experimental data.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ L = \frac{bp \times 10.5 \times [R]}{MW} \]

Where:

Explanation: Trouton's rule states that the entropy of vaporization is approximately constant for many liquids at their boiling points.

3. Importance of Specific Latent Heat Calculation

Details: Knowing the specific latent heat is crucial for designing distillation systems, refrigeration cycles, and other phase-change processes.

4. Using the Calculator

Tips: Enter the boiling point in Kelvin and molecular weight in kg. Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is Trouton's rule?
A: It's an empirical rule stating that the entropy of vaporization is approximately 10.5 times the universal gas constant for many liquids.

Q2: How accurate is this calculation?
A: It provides a reasonable estimate (within 10-20%) for many non-polar liquids but may be less accurate for polar or associating liquids.

Q3: What units should I use for molecular weight?
A: The calculator expects kg (SI units), but you can use g/mol if you multiply the result by 1000.

Q4: Can I use this for any substance?
A: It works best for non-polar liquids with boiling points between 100-1000K. It's less accurate for water, alcohols, or other associating liquids.

Q5: Why is the universal gas constant included?
A: It converts the entropy term (10.5[R]) into energy units, making the result dimensionally consistent.

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