Sequence Number: 1
Atomic Weight: 1.00794
Temperature of Melting: -255.34
Temperature of Boiling: -252.87
Electrons by Layers: 1
Isotopes: 3
Atomic Radius: 0.79
Brief History: Hydrogen is the lightest element. It is by far the most abundant element in the universe and makes up about about 90% of the universe by weight. Hydrogen as water (H2O) is absolutely essential to life and it is present in all organic compounds. Hydrogen gas was used in lighter-than-air balloons for transport but is far too dangerous because of the fire risk (Hindenburg).
