Mendelevium is a synthetic element that was first synthesized by bombarding einsteinium-253 with alpha particles in a cyclotron. It is one of the actinides, a group of elements with atomic numbers between 89 and 103, and is highly radioactive.

The most stable isotope of Mendelevium is Mendelevium-258, which has a half-life of just over 50 days. It has been produced in very small quantities in nuclear reactors, but is generally produced by bombarding lighter elements with heavy nuclei in a particle accelerator.

Mendelevium is named after Dmitry Mendeleev, the father of the periodic table. Its discovery helped to confirm the validity of Mendeleev’s predictions of the properties of elements that had not yet been discovered.

Because of its radioactive and highly toxic properties, there are currently no practical applications for Mendelevium outside of scientific research. It is primarily used for study and research purposes in universities and national laboratories.