Input interpretation
period 1 elements | melting point
Results
hydrogen | -259.14 °C (degrees Celsius) helium | (data not available)
period 1 elements | melting point | -259.14 °C (degrees Celsius) (median) (based on 1 values; 1 unavailable)
Plot
Plot
Unit conversions for median melting point -259.14 °C
14.01 K (kelvins)
-434.45 °F (degrees Fahrenheit)
25.22 °R (degrees Rankine)
-207.31 °Ré (degrees Réaumur)
-128.55 °Rø (degrees Rømer)
Comparison for median melting point -259.14 °C
≈ melting point of hydrogen (-259.14 °C)
11.84 °C above (lower) lambda point of overbound superfluid helium (at 0.0497 atmospheres) (2.172 K)
12.3 °C above (upper) lambda point of overbound superfluid helium (at 29.8 atmospheres) (1.76 K)
Corresponding quantities
Thermodynamic energy E from E = kT: | 1.2 meV (millielectronvolts)
Blackbody energy flux Φ from Φ = σT^4: | 0.0022 W/m^2 (watts per square meter)
Thermodynamic properties
| hydrogen | helium phase at STP | gas | gas melting point | -259.14 °C | boiling point | -252.87 °C | -268.93 °C critical temperature | 32.97 K | 5.19 K critical pressure | 1.293 MPa | 0.227 MPa molar heat of fusion | 0.558 kJ/mol | 0.02 kJ/mol molar heat of vaporization | 0.452 kJ/mol | 0.083 kJ/mol specific heat at STP | 14300 J/(kg K) | 5193.1 J/(kg K) adiabatic index | 7/5 | 5/3 (properties at standard conditions)