What Is the Atomic Mass of Hydrogen?

It has a melting point of -434.81 degrees Fahrenheit, and the boiling point is -423.17 degrees Fahrenheit. This element is the most abundant in the universe, and approximately 90 percent of the known universe is made up of hydrogen.

Hydrogen combines with many other elements to produce different compounds like ammonia, water, hydrogen peroxide and methane. Hydrogen does have isotopes, which are protium (H-1), deuterium (H-2) and tritium (H-3). Tritium has a half-life of 12.3 years.