Water Boiling Point Temperature Pressure Calculator

Boiling Point Equation:

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

Reference Temperature (T₀):

Enthalpy of Vaporization (ΔHvap):

J/mol

Pressure (P):

Reference Pressure (P₀):

Boiling Point (Tb):

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1. What is the Boiling Point Equation?

The boiling point equation calculates the boiling temperature of water at different pressures using the Clausius-Clapeyron relation. It provides an accurate estimation of how boiling point changes with atmospheric pressure variations.

2. How Does the Calculator Work?

The calculator uses the boiling point 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 (K)
\( T_0 \) — Reference temperature (K)
\( R \) — Gas constant (8.314 J/mol·K)
\( \Delta H_{vap} \) — Enthalpy of vaporization (J/mol)
\( P \) — Pressure (Pa)
\( P_0 \) — Reference pressure (Pa)

Explanation: The equation describes how the boiling temperature of a liquid changes with pressure, based on thermodynamic principles.

3. Importance of Boiling Point Calculation

Details: Accurate boiling point calculation is crucial for various applications including cooking at high altitudes, industrial processes, chemical engineering, and meteorological studies where pressure conditions vary.

4. Using the Calculator

Tips: Enter reference temperature (typically 373.15 K for water), enthalpy of vaporization (typically 40660 J/mol for water), pressure, and reference pressure (typically 101325 Pa). All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: Why does boiling point change with pressure?
A: Boiling occurs when vapor pressure equals atmospheric pressure. At lower pressures, less energy is needed for vaporization, so boiling occurs at lower temperatures.

Q2: What are typical values for water?
A: At sea level (101325 Pa), water boils at 373.15 K (100°C). The enthalpy of vaporization is approximately 40660 J/mol at boiling point.

Q3: How does altitude affect boiling point?
A: Higher altitudes have lower atmospheric pressure, causing water to boil at lower temperatures (approximately 1°C decrease per 300m elevation).

Q4: Can this equation be used for other liquids?
A: Yes, but you need the appropriate reference values (T₀, P₀, and ΔHvap) for the specific liquid.

Q5: How accurate is this calculation?
A: The equation provides good approximations for most practical purposes, though extreme conditions may require more complex models.