1. What is Hydrogen Gas Density?

Definition: This calculator estimates the density of hydrogen gas (H₂) based on pressure and temperature using the ideal gas law.

Purpose: It helps scientists, engineers, and students determine the density of hydrogen gas under various conditions.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \rho \) — Density of H₂ gas (kg/m³)
• \( P \) — Pressure (Pascals)
• \( M \) — Molar mass of H₂ (0.002 kg/mol)
• \( R \) — Universal gas constant (8.314 J/(mol·K))
• \( T \) — Temperature (Kelvin)

Explanation: The formula is derived from the ideal gas law, relating pressure, volume, and temperature of an ideal gas.

3. Importance of H₂ Density Calculation

Details: Knowing hydrogen density is crucial for fuel cell design, hydrogen storage systems, and various industrial applications.

4. Using the Calculator

Tips: Enter the pressure in Pascals (default 101325 Pa for STP) and temperature in Kelvin (default 273.15 K for 0°C). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the density of H₂ at STP?
A: At standard temperature and pressure (273.15 K, 101325 Pa), H₂ density is approximately 0.0899 kg/m³.

Q2: Why is hydrogen less dense than air?
A: Hydrogen molecules (H₂) are much lighter than nitrogen (N₂) and oxygen (O₂) molecules that make up air.

Q3: How does temperature affect H₂ density?
A: Density decreases as temperature increases (at constant pressure), following the inverse relationship in the ideal gas law.

Q4: How does pressure affect H₂ density?
A: Density increases linearly with pressure (at constant temperature), as shown in the formula.

Q5: Is this calculation accurate for real hydrogen gas?
A: It's accurate for ideal gas behavior. For high pressures or low temperatures, real gas corrections may be needed.