Nomenclature of Elements Above 100
The discovery and naming of chemical elements with atomic numbers above 100 is a fascinating aspect of modern chemistry. These elements are typically synthesized in laboratories and are not found naturally on Earth. Due to their synthetic nature, only a few atoms of these elements are usually obtained at a time, making their study and characterization a challenging task that requires sophisticated equipment and techniques.
Historical Context
In the past, the discovery of new elements often led to disputes over naming rights. For instance, both American and Soviet scientists claimed the discovery of element 104. The Americans named it Rutherfordium, while the Soviets called it Kurchatovium. To avoid such conflicts, the International Union of Pure and Applied Chemistry (IUPAC) established a systematic approach to naming these elements.
IUPAC Naming System
The IUPAC recommended that until a new element's discovery is confirmed and its name officially recognized, a temporary systematic nomenclature should be used. This nomenclature is derived directly from the atomic number of the element using specific numerical roots for each digit from 0 to 9. These roots are combined in order of the digits that make up the atomic number, followed by the suffix "ium."
Numerical Roots
The numerical roots used in the IUPAC system are as follows:
- 0 - nil
- 1 - un
- 2 - bi
- 3 - tri
- 4 - quad
- 5 - pent
- 6 - hex
- 7 - sept
- 8 - oct
- 9 - enn
Examples of Nomenclature
Using this system, elements with atomic numbers above 100 are named as follows:
- 101 - Unnilunium (Unu)
- 102 - Unnilbium (Unb)
- 103 - Unniltrium (Unt)
- 104 - Unnilquadium (Unq)
- 105 - Unnilpentium (Unp)
- 106 - Unnilhexium (Unh)
- 107 - Unnilseptium (Uns)
- 108 - Unniloctium (Uno)
- 109 - Unnilennium (Une)
Official Names
Once an element's discovery is confirmed, it is given an official name. For example:
- 101 - Mendelevium (Md)
- 102 - Nobelium (No)
- 103 - Lawrencium (Lr)
- 104 - Rutherfordium (Rf)
- 105 - Dubnium (Db)
- 106 - Seaborgium (Sg)
- 107 - Bohrium (Bh)
- 108 - Hassium (Hs)
- 109 - Meitnerium (Mt)
Conclusion
The systematic nomenclature provided by IUPAC ensures clarity and consistency in the naming of newly discovered elements. This approach not only helps avoid disputes but also provides a logical method for naming elements based on their atomic numbers. As scientific techniques advance, the discovery of new elements continues to expand our understanding of the periodic table and the fundamental building blocks of matter.