Platinum is a dense, malleable, ductile, highly unreactive, precious, silverish-white transition metal. Platinum is one of the least reactive metals. It has remarkable resistance to corrosion, even at high temperatures, and is therefore considered a noble metal. Platinum is used in catalytic converters, laboratory equipment, electrical contacts and electrodes, platinum resistance thermometers, dentistry equipment, and jewelry.
Protons and Neutrons in Platinum
Platinum is a chemical element with atomic number 78 which means there are 78 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 Platinum are 194, 195, 196, 198.
Main Isotopes of Platinum
Platinum occurs in 6 natural isotopes: 190Pt, 192Pt, 194Pt, 195Pt, 196Pt and 198Pt. 190Pt is very slightly radioactive, decaying by alpha decay with a half-life of 6.5×1011 years. 195Pt is the most common isotope, having a natural abundance of approximately 33%.
Platinum-190 is composed of 78 protons, 112 neutrons, and 78 electrons.
Platinum-192 is composed of 78 protons, 114 neutrons, and 78 electrons.
Platinum-194 is composed of 78 protons, 116 neutrons, and 78 electrons.
Platinum-195 is composed of 78 protons, 117 neutrons, and 78 electrons.
Platinum-196 is composed of 78 protons, 118 neutrons, and 78 electrons.
Platinum-198 is composed of 78 protons, 120 neutrons, and 78 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 Platinum is 78. 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 Platinum is [Xe] 4f14 5d9 6s1.
Possible oxidation states are +2,4.
Most Common Application of Platinum
Hexachloroplatinic acid is probably the most important platinum compound, as it serves as the precursor for many other platinum compounds. By itself, it has various applications in photography, zinc etchings, indelible ink, plating, mirrors, porcelain coloring, and as a catalyst.
|Number of protons||78|
|Number of neutrons (typical isotopes)||194, 195, 196, 198|
|Number of electrons||78|
|Electron configuration||[Xe] 4f14 5d9 6s1|
Properties of other elements