Ethanol Boiling Point Under Vacuum Calculator

Ethanol Boiling Point Equation:

\[ T_b = \frac{1}{\frac{1}{T_0} - \frac{R}{\Delta H_{vap}} \ln \left( \frac{P}{P_0} \right)} \]

Boiling Point (T_b):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Ethanol Boiling Point Under Vacuum Equation?

The ethanol boiling point under vacuum equation calculates the boiling temperature of ethanol at reduced pressures using the Clausius-Clapeyron relation. This is particularly useful in distillation processes and chemical engineering applications where pressure affects boiling points.

2. How Does the Calculator Work?

The calculator uses the equation:

\[ T_b = \frac{1}{\frac{1}{T_0} - \frac{R}{\Delta H_{vap}} \ln \left( \frac{P}{P_0} \right)} \]

Where:

\( T_b \) — Boiling point under vacuum (K)
\( T_0 \) — Standard boiling point of ethanol (351.4 K)
\( R \) — Gas constant (8.314 J/mol·K)
\( \Delta H_{vap} \) — Enthalpy of vaporization of ethanol (38560 J/mol)
\( P \) — Vacuum pressure (Pa)
\( P_0 \) — Standard pressure (101325 Pa)

Explanation: The equation describes how the boiling point of ethanol decreases as the pressure decreases, following thermodynamic principles.

3. Importance of Boiling Point Calculation

Details: Accurate boiling point calculation under vacuum is crucial for distillation processes, solvent recovery, chemical synthesis, and various industrial applications where temperature-sensitive materials are involved.

4. Using the Calculator

Tips: Enter the vacuum pressure in Pascals (Pa). The pressure must be a positive value greater than zero. The calculator will compute the corresponding boiling point of ethanol at that pressure.

5. Frequently Asked Questions (FAQ)

Q1: Why does boiling point decrease under vacuum?
A: Reducing pressure lowers the energy required for molecules to escape the liquid phase, thus decreasing the boiling temperature.

Q2: What is the standard boiling point of ethanol?
A: The standard boiling point of ethanol at atmospheric pressure (101325 Pa) is 351.4 K (78.3°C).

Q3: Can this equation be used for other liquids?
A: The equation form is general, but specific constants (T₀, ΔH_vap) must be used for each substance.

Q4: What are typical vacuum pressure ranges?
A: Vacuum pressures can range from atmospheric pressure down to very low pressures (e.g., 100-1000 Pa) depending on the application.

Q5: How accurate is this calculation?
A: The calculation provides a good estimate, but actual results may vary slightly due to impurities, measurement accuracy, and non-ideal behavior.