New Elements
Since the dawn of time, man has been fascinated by the elements. The earliest known periodic table was devised by the Ancient Greeks, who identified four elements: fire, earth, air and water. But it wasn’t until the 18th century that scientists began to systematically study and classify the elements. In 1789, Antoine Lavoisier published a list of 33 elements, which included oxygen, hydrogen, nitrogen and carbon. This was the first time that elements were grouped together according to their chemical properties.
Today, there are 118 known elements. Of these, 94 occur naturally on Earth while 24 have been created artificially in laboratories. The most recent addition to the periodic table is Flerovium (Fl), which was synthesized in 2014. Here we take a look at some of the other new additions to the periodic table over the past few decades…
Californium (Cf)
Discovered in 1950 by Stanley Grafton Thompson and Albert Ghiorso at Berkeley Lab in California, Cf is a radioactive actinide element with an atomic number of 98. It is named after the state of California where it was discovered. Californium is used in portable X-ray fluorescence analyzers for detection of heavy metals in soil and water samples; as well as neutron sources for oil well logging and nondestructive testing equipment.
Berkelium (Bk)
Also discovered at Berkeley Lab in 1949 by Thompson, Ghiorso and their team; Bk is a radioactive actinide with an atomic number of 97. It is named after Berkeley where it was discovered – making it one of only three elements named after US cities (the other two being californium and americium). Berkelium is used as a source material for producing Curium (Cm), another radioactive element used in nuclear weapons research.
Americium (Am) Discovered in 1944 at Chicago University by Glenn Seaborg – Am is a synthetic radioactive actinide metal with an atomic number 95. Its name comes from America – specifically Seaborg’s home city Chicago where he discovered it during World War II while working on the Manhattan Project (developing nuclear weapons). Today americium is used mainly in smoke detectors; however its radioisotopes have also found use as power sources for space satellites and pacemakers