Balloon Inflation Simulation
Real-Time Property Charts
Numeric Properties
Hydrogen has the highest energy content per unit mass of any fuel, making it extremely efficient for energy storage.
| Fuel | Energy Density (MJ/kg) | Relative to Hydrogen |
|---|---|---|
| Hydrogen (H₂) | 142 | 100% |
| Natural Gas (Methane) | 55 | 39% |
| Propane | 49.6 | 35% |
| Gasoline | 46.4 | 33% |
| Diesel | 45.6 | 32% |
| Coal | 30 | 21% |
| Wood | 16.2 | 11% |
| Lithium-ion Battery | 0.9 | 0.6% |
Hydrogen diffuses much faster than other gases due to its low molecular mass. This has important implications for both safety and practical applications.
According to Graham's Law, the rate of diffusion of a gas is inversely proportional to the square root of its molecular mass.
| Gas | Molar Mass (g/mol) | Relative Diffusion Rate (to H₂) |
|---|---|---|
| Hydrogen (H₂) | 2.016 | 100% |
| Helium (He) | 4.003 | 71% |
| Methane (CH₄) | 16.04 | 35% |
| Nitrogen (N₂) | 28.01 | 27% |
| Oxygen (O₂) | 32.00 | 25% |
| Carbon Dioxide (CO₂) | 44.01 | 21% |
| Propane (C₃H₈) | 44.10 | 21% |
Hydrogen has unique combustion properties that set it apart from other fuels.
| Property | Hydrogen | Methane | Propane |
|---|---|---|---|
| Flammability Range (% in air) | 4-75% | 5-15% | 2.1-9.5% |
| Ignition Energy (mJ) | 0.02 | 0.29 | 0.26 |
| Flame Temperature (°C) | 2045 | 1875 | 1980 |
| Flame Visibility | Nearly invisible | Blue visible | Blue visible |
| Combustion Product | Water (H₂O) | CO₂ + H₂O | CO₂ + H₂O |
2H₂ + O₂ → 2H₂O + Energy (Heat)
This reaction is what powers hydrogen fuel cells and produces zero carbon emissions — only water as a by-product.
Understanding hydrogen's physical properties is critical for safe handling and use:
| Safety Factor | Description | Safety Implication |
|---|---|---|
| Low Density | 14 times lighter than air | Disperses rapidly upward in air rather than pooling near the ground (unlike natural gas) |
| High Diffusivity | Diffuses 3.8x faster than natural gas | Reduces concentration quickly but can pass through smaller openings than other gases |
| Wide Flammability Range | 4-75% in air (vs. 5-15% for methane) | Can ignite over a wider range of concentrations |
| Low Ignition Energy | 0.02 mJ (vs. 0.29 mJ for methane) | Can be ignited more easily by sparks or static electricity |
| Invisible Flame | Burns with a nearly invisible flame in daylight | Difficult to detect a hydrogen fire visually, requiring special sensors |
| Embrittlement | Can weaken certain metals over time | Requires special materials for long-term storage and transport |
Relative risk visualization for different properties compared to natural gas:
Despite these concerns, hydrogen can be handled safely with proper engineering controls and procedures. Its rapid dispersal rate is a significant safety advantage over denser fuels like propane or gasoline which can pool and create larger fire hazards.
Hydrogen's physical and chemical properties make it ideal for numerous applications:
| Application | Key Property Utilized | Benefits |
|---|---|---|
| Fuel Cells | High energy density, clean combustion | Zero emission power generation, high efficiency (60%+) |
| Rocket Fuel | High energy-to-weight ratio | Highest specific impulse of any chemical rocket fuel |
| Energy Storage | Convertible from/to electricity | Long-term storage of renewable energy |
| Industrial Processes | Reactivity as reducing agent | Used in metal production, food processing, electronics |
| Transportation | Zero carbon emissions, high energy density | Fuel for vehicles with only water as emission |
| Cooling | High thermal conductivity | Used as coolant in power generators |
| Metal Production | Reducing properties | Used to create cleaner steel production processes |
The "hydrogen economy" leverages hydrogen's unique properties as a clean, versatile energy carrier:
Ideal Gas Law: PV = nRT
Density Formula: ρ = m/V = MP/RT
Buoyancy Force: F = (ρair - ρgas)Vg
Graham's Law of Diffusion: Rate₁/Rate₂ = √(M₂/M₁)
The rate of diffusion of a gas is inversely proportional to the square root of its molar mass.
| Gas | Molar Mass (g/mol) | Density at STP (kg/m³) | Specific Heat Capacity (J/(kg·K)) |
|---|---|---|---|
| Hydrogen (H₂) | 2.016 | 0.0899 | 14,304 |
| Helium (He) | 4.003 | 0.1785 | 5,193 |
| Methane (CH₄) | 16.04 | 0.6569 | 2,220 |
| Nitrogen (N₂) | 28.01 | 1.2506 | 1,040 |
| Oxygen (O₂) | 32.00 | 1.4290 | 919 |
| Carbon Dioxide (CO₂) | 44.01 | 1.9769 | 846 |
| Propane (C₃H₈) | 44.10 | 2.0098 | 1,670 |
| Air (average) | 28.97 | 1.2250 | 1,005 |
Other Constants:
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