Scandium is a silvery-white metallic d-block element, it has historically been sometimes classified as a rare-earth element, together with yttrium and the lanthanides.
The main application of scandium by weight is in aluminium-scandium alloys for minor aerospace industry components.
The world production of scandium is in the order of 15-20 tonnes per year, in the form of scandium oxide.
Protons and Neutrons in Scandium
Scandium is a chemical element with atomic number 21 which means there are 21 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 Scandium are 45.
Main Isotopes of Scandium
In nature, scandium is found exclusively as the isotope 45Sc, which has a nuclear spin of 7/2; this is its only stable isotope. Twenty-five radioisotopes have been characterized, with the most stable being 46Sc with a half-life of 83.8 days
Scandium-45 is composed of 21 protons, 24 neutrons, and 21 electrons.
Scandium-46 is composed of 21 protons, 25 neutrons, and 21 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 Scandium is 21. 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 Scandium is [Ar] 3d1 4s2.
Possible oxidation states are +3.
The properties of scandium compounds are intermediate between those of aluminium and yttrium. A diagonal relationship exists between the behavior of magnesium and scandium, just as there is between beryllium and aluminium. In the chemical compounds of the elements in group 3, the predominant oxidation state is +3.
Most Common Alloy of Scandium
The main application of scandium by weight is in aluminium-scandium alloys for minor aerospace industry components. These alloys contain between 0.1% and 0.5% of scandium. Sc drastically improves Al alloys, increasing strength, corrosion resistance and weldability.
|Number of protons||21|
|Number of neutrons (typical isotopes)||45|
|Number of electrons||21|
|Electron configuration||[Ar] 3d1 4s2|
Properties of other elements