Titanium is a lustrous transition metal with a silver color, low density, and high strength. The two most useful properties of the metal are corrosion resistance and strength-to-density ratio, the highest of any metallic element. The corrosion resistance of titanium alloys at normal temperatures is unusually high.
The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. Kroll’s process involved reduction of titanium tetrachloride (TiCl4), first with sodium and calcium, and later with magnesium, under an inert gas atmosphere.
Protons and Neutrons in Titanium
Titanium is a chemical element with atomic number 22 which means there are 22 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 Titanium are 46-50.
Main Isotopes of Titanium
Naturally occurring titanium is composed of five stable isotopes: 46Ti, 47Ti, 48Ti, 49Ti, and 50Ti, with 48Ti being the most abundant (73.8% natural abundance). The isotopes of titanium range in atomic mass from 38.01 u (38Ti) to 62.99 u (63Ti).
Titanium-46 is composed of 22 protons, 24 neutrons, and 22 electrons.
Titanium-47 is composed of 22 protons, 25 neutrons, and 22 electrons.
Titanium-48 is composed of 22 protons, 26 neutrons, and 22 electrons.
Titanium-49 is composed of 22 protons, 27 neutrons, and 22 electrons.
Titanium-50 is composed of 22 protons, 28 neutrons, and 22 electrons.
Titanium-44 is composed of 22 protons, 22 neutrons, and 22 electrons. Titanium-44 is produced in relative abundance the alpha process in stellar nucleosynthesis and the early stages of supernova explosions. The age of supernovae may be determined through measurements of gamma ray emissions from titanium-44 and its abundance.
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 Titanium is 22. 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 Titanium is [Ar] 3d2 4s2.
Possible oxidation states are +2,3,4.
The +4 oxidation state dominates titanium chemistry, but compounds in the +3 oxidation state are also common. Because of its high oxidation state, titanium(IV) compounds exhibit a high degree of covalent bonding. Unlike most other transition metals, simple aquo Ti(IV) complexes are unknown.
Most Common Alloy of Titanium
Generally, Ti-6Al-4V is used in applications up to 400 degrees Celsius. It has a density of roughly 4420 kg/m3. It is significantly stronger than commercially pure titanium (grades 1-4) due to its possibility to be heat treated. This grade is an excellent combination of strength, corrosion resistance, weld and fabricability It is the prime choice for many fields of applications:
- Aircraft turbines
- Engine components
- Aircraft structural components
- Aerospace fasteners
- High-performance automatic parts
- Marine applications
|Number of protons||22|
|Number of neutrons (typical isotopes)||46-50|
|Number of electrons||22|
|Electron configuration||[Ar] 3d2 4s2|