As a chemical element, hydrogen comes first in The Periodic Table.
Hydrogen is the first element produced by the universe, it is the oldest, most widespread, and the simplest element in the universe. The early universe consisted almost exclusively of hydrogen. In theory, other elements have also evolved from hydrogen, so hydrogen naturally has a function of reductive.
The universe originated from the element hydrogen. Hydrogen not only participates in the origin of the universe, but also participates in the origin of life, and has played an active role in the evolution of organisms. Therefore, it is possible that the sensitivity and dependence to hydrogen are preserved in the DNA of organisms. Hydrogen and oxygen combine to form water, and water is recognized as the source of all lives that embraces and nurses human beings. Hence, the hydrogen element may hide huge biology secrets.
Hydrogen is the smallest molecule in nature. When we breathe in hydrogen, the hydrogen can enter the body through respiratory tract, and then easily spread to various parts of the body, and even enter the interior of the cells in various parts.
Hydrogen molecules are very small, it easily to penetrate rubber, plastic and other materials. For example, other materials, such as glass, it won't reserve hydrogen molecules. Under high temperature and pressure, hydrogen can penetrate many metals and even steel plates tens of centimeters thick, while the better material for storing hydrogen is aluminum alloy.
