With a standard atomic weight of circa 1.008, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass. The largest single use of hydrogen in the world is in ammonia manufacture, which consumes about two-thirds of the world’s hydrogen production. Hydrogen is versatile and can be utilized in various ways. In industry, hydrogen is often produced using natural gas, which involves the removal of hydrogen from hydrocarbons at very high temperatures, with about 95% of hydrogen production coming from steam reforming around year 2000.
Protons and Neutrons in Hydrogen
Hydrogen is a chemical element with atomic number 1 which means there are 1 protons in its nucleus. Total number of protons in the nucleus is called the atomic number of the atom and is given the symbol Z. The total electrical charge of the nucleus is therefore +Ze, where e (elementary charge) equals to 1,602 x 10-19 coulombs.
The total number of neutrons in the nucleus of an atom is called the neutron number of the atom and is given the symbol N. Neutron number plus atomic number equals atomic mass number: N+Z=A. The difference between the neutron number and the atomic number is known as the neutron excess: D = N – Z = A – 2Z.
For stable elements, there is usually a variety of stable isotopes. Isotopes are nuclides that have the same atomic number and are therefore the same element, but differ in the number of neutrons. Mass numbers of typical isotopes of Hydrogen are 1; 2.
Common Isotopes of Hydrogen
The most abundant isotope, hydrogen-1, protium, or light hydrogen, contains no neutrons and is simply a proton and an electron. Protium is stable and makes up 99.985% of naturally occurring hydrogen atoms.
Deuterium contains one neutron and one proton in its nucleus. Deuterium is stable and makes up 0.0156% of naturally occurring hydrogen and is used in industrial processes like nuclear reactors and Nuclear Magnetic Resonance.
Tritium or hydrogen-3 (symbol T or 3H) is a rare and radioactive isotope of hydrogen. The nucleus of tritium (sometimes called a triton) contains one proton and two neutrons.
Electrons and Electron Configuration
The number of electrons in an electrically-neutral atom is the same as the number of protons in the nucleus. Therefore, the number of electrons in neutral atom of Hydrogen is 1. Each electron is influenced by the electric fields produced by the positive nuclear charge and the other (Z – 1) negative electrons in the atom.
Since the number of electrons and their arrangement are responsible for the chemical behavior of atoms, the atomic number identifies the various chemical elements. The configuration of these electrons follows from the principles of quantum mechanics. The number of electrons in each element’s electron shells, particularly the outermost valence shell, is the primary factor in determining its chemical bonding behavior. In the periodic table, the elements are listed in order of increasing atomic number Z.
Electron configuration of Hydrogen is 1s1.
Possible oxidation states are +1,-1.
Hydrogen plays a particularly important role in acid–base reactions because most acid-base reactions involve the exchange of protons between soluble molecules. In ionic compounds, hydrogen can take the form of a negative charge (i.e., anion) when it is known as a hydride, or as a positively charged (i.e., cation) species denoted by the symbol H+. The hydrogen cation is written as though composed of a bare proton, but in reality, hydrogen cations in ionic compounds are always more complex.
Most Common Chemical Compound of Hydrogen
Water is the most common chemical compound of hydrogen. Its chemical formula is H2O, meaning that each of its molecules contains one oxygen and two hydrogen atoms, connected by covalent bonds.Two hydrogen atoms attached one oxygen atom at angle of 104.45°.
|Number of protons||1|
|Number of neutrons (typical isotopes)||1; 2|
|Number of electrons||1|
Properties of other elements