halogod123

 Francium occurs as a result of α disintegration of actinium. Francium is found in uranium minerals, and can be made artificially by bombarding thorium with protons. It is the most unstable of the first 101 elements. The longest lived isotope, ²²³Fr, a daughter of ²²⁷Ac, has a half-life of 22 minutes. This is the only isotope of francium occurring in nature, but at most there is only 20-30 g of the element present in the earth’s crust at any one time. No weighable quantity of the element has been prepared or isolated. There are about 20 known isotopes.

 Francium is too rare and too reactive for us to have concrete data, but you can project the type of reaction by looking at the reactions of the other group 1/IA metals. When the metals come into contact with water, a single replacement reaction occurs. This produces a hydroxide compound containing the metal and free Hydrogen gas (which rapidly expands). As you progress down the IA column greater ammounts of Hydrogen gas are produced and the reaction is more and more violent. Two grams of Cesium into a tub of water produces a violent enough reaction to blow up the tub. It stands to reason that the reaction of Francium and water would be significantly greater.

Isolation: francium is vanishingly rare and is found only as very small traces in some uranium minerals. It has never been isolated as the pure element. As it is so radioactive, any amount formed would decompose to other elements.

Actinium decays by β decay most of the time but about 1% of the decay is by α decay. The “daughter” element of this reaction, which used to be called actinium-K, is now recognized as ²²³₈₇Fr - the longest-lived isotope of actinium with a half life of about 22 minutes.

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