|
|
| Hydrogen | |
| Electron Configuration | 1 |
| Electron Configuration | 1s1 |
| Ground state | 2S1/2 |
| Atomic Volume | 14.4 g/cm3 |
| Electronegativity | 2.20 |
| Magnetic ordering | No data |
| Mass magnetic susceptibility | -2.48 x 10-8 |
| Molar magnetic susceptibility | -2.5 x 10-11 |
| Speed of sound | 1310 m s-1 |
 Thermal Properties |
|
| Enthalpy of Atomization | 217.6 kJ mol-1 @25°C |
| Enthalpy of Fusion | 0.12 kJ mol-1 |
| Enthalpy of Vaporisation | 0.46 kJ mol-1 |
| Heat Capacity | 28.836 (H2) J mol-1 K-1 |
| Thermal Conductivity | 180.5 W m-1 K-1 |
| Thermal Expansion | No data. |
| Electrical Properties |
|
| Electrical resistivity | No data. |
| Electrical conductivity | No data. |
| Chemical Properties |
|
| Electrochemical Equivalent | 0.037605 g Ah-1 |
| Valence Electron Potential (-eV) | 1200 |
| Ionization Potential | |
 First
|
13.598 |
| Incompatibilities | Metals, oxidizing materials, metal oxides, combustible materials, halogens, metal salts, halo carbons. |
| Flammability |
|
| Highly flammable gas
|
|
| Autoignition temp
|
773K (500°C) |
| Flashpoint
|
20K (-253°C) Theoretical |
| Optical Properties |
|
| Refractive Index (gas) | 1.000132 |
| Refractive Index (liquid) | 1.12 |
| Energy Levels |
|
| Kα1 (intensity 100) |
0.012 KeV |
| Atomic Radii |
|
| Empirical
|
25 pm |
| Bohr Radius
|
53 pm |
| Covalent Radius
|
37 pm |
| Van der Waals
|
120 pm |
| Triple covalent
|
No data. |
| Metallic
|
No data. |
| Ionic Radii (Å) |
||||
| Charge | Coordination | Crystal | Ionic | Key |
| 1 | I | -0.24 | -0.38 | |
| II | -0.04 | -0.18 | ||
| 1 (D) | II | 0.04 | -0.1 | |
| -1 (OH) | II | 1.18 | 1.32 | |
| III | 1.2 | 1.34 | ||
| IV | 1.21 | 1.35 | E | |
| VI | 1.23 | 1.37 | E | |
| R, From r3 vs V plots. |
| C, Calculated from bond length - bond strength equations. |
| E, Estimated. |
| *, Most Reliable. |
| M, From Metallic Oxides. |
| A, Ahrens (1952) Ionic radius. |
| P, Pauling's (1960) Crystal Radius. |
| Oxidation States |
|
| Main
|
H+1 |
| Other
|
H0, H-1 |
Ionisation Energies (kJ mol-1)  |
|
| M - M+ |
1312 |
| Covalent Bonds (kJ mol-1) |
|
| H-H
|
454 |
| H-F
|
566 |
| H-Cl
|
431 |
| H-Br
|
366 |
| H-I
|
299 |
| Vapour Pressure |
||||||
| P (Pa) | 1 | 10 | 100 | 1K | 10K | 100K |
| T (K) | 15 | 20 | ||||
| Crystal Structure |
|
| Structure
|
Hexagonal close packed |
 |
a = 470 pm |
| b = 470 pm | |
| c = 340 pm | |
| α = 90° | |
| β = 90° | |
| γ = 120° | |