Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them. More than half the supply of palladium and its congener platinum is used in catalytic converters.
Protons and Neutrons in Palladium
Palladium is a chemical element with atomic number 46 which means there are 46 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 Palladium are 102, 104-106, 108, 110.
Main Isotopes of Palladium
Palladium occurs in 7 natural isotopes: 102Pd, 104Pd, 105Pd, 106Pd, 107Pd, 108Pd and 110Pd. Of these, 107Pd is trace radioisotope, decaying by beta decay with a half-life of 6.5×106 years. 106Pd is the most common isotope, having a natural abundance of approximately 27%.
Palladium-102 is composed of 46 protons, 56 neutrons, and 46 electrons.
Palladium-104 is composed of 46 protons, 58 neutrons, and 46 electrons.
Palladium-105 is composed of 46 protons, 59 neutrons, and 46 electrons.
Palladium-106 is composed of 46 protons, 60 neutrons, and 46 electrons.
Palladium-107 is composed of 46 protons, 61 neutrons, and 46 electrons.
Palladium-108 is composed of 46 protons, 62 neutrons, and 46 electrons.
Palladium-110 is composed of 46 protons, 64 neutrons, and 46 electrons.
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 Palladium is 46. 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 Palladium is [Kr] 4d10.
Possible oxidation states are +2,4.
Most Common Application of Palladium
More than half the supply of palladium and its congener platinum is used in catalytic converters, which convert as much as 90% of the harmful gases in automobile exhaust into less noxious substances.
|Number of protons||46|
|Number of neutrons (typical isotopes)||102, 104-106, 108, 110|
|Number of electrons||46|
|Electron configuration||[Kr] 4d10|
Properties of other elements