1. What is Vapour Pressure?

Vapour pressure is the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases at a given temperature. For water, it represents the maximum amount of water vapor the air can hold at a specific temperature.

2. How Does the Calculator Work?

The calculator uses the Magnus formula:

Where:

• \( e_s \) — Saturation vapour pressure (hPa)
• \( T \) — Temperature (°C)
• \( \exp \) — Exponential function

Explanation: The Magnus formula provides an empirical relationship between temperature and the saturation vapour pressure of water, accurate for temperatures between -50°C and 100°C.

3. Importance of Vapour Pressure Calculation

Details: Vapour pressure calculations are essential in meteorology, HVAC systems, industrial processes, and environmental science for understanding humidity, evaporation rates, and atmospheric conditions.

4. Using the Calculator

Tips: Enter temperature in degrees Celsius. The default value is set to 60°C as requested, but you can calculate for any temperature between -50°C and 100°C.

5. Frequently Asked Questions (FAQ)

Q1: Why is 60°C a significant temperature for vapour pressure calculation?
A: 60°C is often used in industrial processes, sterilization, and certain scientific applications where precise humidity control is important.

Q2: How accurate is the Magnus formula?
A: The Magnus formula provides good accuracy (±0.1% to ±0.5%) for temperatures between -50°C and 100°C, which covers most practical applications.

Q3: What are the units of vapour pressure?
A: Vapour pressure is typically measured in hectopascals (hPa) or millibars (mb), which are equivalent units of pressure.

Q4: How does vapour pressure change with temperature?
A: Vapour pressure increases exponentially with temperature, meaning that warmer air can hold significantly more water vapor than cooler air.

Q5: What is the relationship between vapour pressure and relative humidity?
A: Relative humidity is the ratio of the actual vapour pressure to the saturation vapour pressure at that temperature, expressed as a percentage.