Highly radioactive elements in the Earth’s crust have never been obtained

Located at the bottom of the periodic table and the most radioactive element in the periodic table, francium is extremely toxic to anyone who comes near it. Its radioactivity is up to 45,000 curies/mg.

In fact, researchers have never been able to observe francium. It has no known applications and does not appear to perform any biological function. It is so rare and short-lived that scientists who want to study the element must create francium themselves by letting neutrons collide with radium or letting protons collide with thorium.

For many years, francium’s existence was only theoretical. It was Dmitri Mendeleev, the father of the periodic table, who first hypothesized that there was an undiscovered alkali metal hidden in the universe with an atomic number of 87. This sparked a race to discover it. mysterious element. Many prominent scientists claimed to have found it, but their results were later refuted.

The only naturally occurring isotope of francium is francium-223 which forms during the radioactive decay of actinium. In 1939, it was first discovered by a French physicist Marguerite Perey working with actinium at the Radium Institute in Paris, who worked as a personal assistant to Marie Curie. Element 87 was later renamed “francium” after Perey’s homeland.

Observations following its discovery revealed that francium-223 has a half-life of just 22 minutes. Meanwhile, uranium-235, a radioactive isotope used as fuel for nuclear power plants, has a half-life of about 700 million years.