Wikijunior:The Elements/Francium
What does it look, feel, taste or smell like?
[edit | edit source]Francium is a very unstable metal. Francium is thought to have a silvery and gray color to it. No one has tasted francium because it is very rare, toxic and radioactive. Scientists cannot study francium directly. It exists only in trace amounts and disappears too quickly. Francium-223, has a half-life of only 22 minutes. Scientists are unable to collect enough to examine. The largest sample ever created contained only about 300,000 atoms—an amount too small to see with the naked eye.
How was it discovered?
[edit | edit source]Francium was discovered in 1939 by Marguerite Perey of the Curie Institute, in Paris, France.
At the time, she was researching the radioactive decay of actinium-227. Her research indicated there was another element hidden in her sample. She deduced the missing element was number 87. Her results were challenged by other scientists. She was not credited with the discovery of francium until 1946.
Francium is the last naturally occurring element that has been discovered. Later discoveries were all synthetic elements created in laboratories. To make synthetic elements, scientists use particle accelerators and nuclear reactors. These machines smash atoms together to create new elements that do not exist in nature.
Where did it name come from?
[edit | edit source]Marguerite Perey named francium after France, her home country.
It was once called eka-caesium. “Eka” is a Sanskrit word meaning “one” (one place below caesium on the periodic table). Eka caesium was a “placeholder” word indicating where a new element would be placed on the periodic table when it was discovered.
After Perey’s discovery, the name “catium” was suggested, but people thought English speakers would associate the name with cats.
Where is it found?
[edit | edit source]There is very little naturally occurring francium on earth. Small amounts of francium are found with uranium and thorium ores. Scientists estimate there are only 20–30 grams of francium in the entire Earth’s crust—less than a handful spread across the whole planet. Francium is found in uranium minerals such as pitchblende (uraninite). Scientists can make synthetic francium in the laboratory. It decays quickly, making it difficult to study.
What are it uses?
[edit | edit source]Francium has a short half-life of about 22 minutes. It is so unstable, it would decompose to other elements quickly. So, there are no known uses for francium based on the research.
Francium is not practical for making things that people use. It may be used in medicine someday. It may be used in the future by geologists to tell the age of rocks. These ideas are not practical today.
Is it dangerous?
[edit | edit source]Francium is very dangerous because it is radioactive. Scientists hypothesize it would react instantly with air (oxidize) and react violently with water (explode).
Intense heat and hydrogen gas would be released. Radioactive contamination would make it very dangerous.
References
[edit | edit source]Did You Know?
- At first, francium had a symbol of Fa but later it became Fr
- Francium is the most unstable of the first 101 elements of the periodic table
- Francium is the second rarest element in the Earth’s crust, next to astatine
Reference ChemistryCool. (n.d.). Francium: Element 87 – Properties, history, and uses. ChemistryCool. https://chemistrycool.com/element/francium
Cook, P. (2020). Introduction to isotopes and environmental tracers as indicators of groundwater flow. Guelph, Ontario, Canada: The Groundwater Project. https://doi.org/10.21083/978-1-7770541-8-2
Periodic Table of Videos. (2020, March 15). Francium: The discovery of the world's most expensive element [Video]. YouTube. https://www.youtube.com/watch?v=OUcoHWWgfDM
Royal Society of Chemistry. (2025). Periodic table. Royal Society of Chemistry. https://periodic-table.rsc.org/
Winter, M. (1993–2025). WebElements: The periodic table on the web. University of Sheffield & WebElements Ltd. https://www.webelements.com