Cesium is a metallic chemical element found on the periodic table of elements under the symbol Cs and with an atomic number of 55. Cesium is a soft, silvery-gold alkali metal that is the most reactive and electropositive element. It is rapidly attacked by air, so it is usually handled under an inert atmosphere. Caesium is a rare element with an estimated abundance of only 3 parts per million in Earth’s crust. However, it is relatively abundant in seas since it is highly soluble in water and can accumulate in marine organisms such as plankton.
The name comes from the Latin word caesius, meaning sky blue, which is the color of the elements first spectral line. Caesium is obtained from pollucite, a silicate ore of caesium and other alkali metals. This ore is converted to caesium chloride or caesium carbonate, which are further treated to obtain the pure element.
Caesium is a monoisotopic element; that is, it has only one stable isotope, which is of mass number 133 and has an isotopic abundance of 100%. Thus, its potential for applications as a neutron absorber is quite limited. Caesium has several uses in industry, the most important being its role in regulating the flow of electric current in some types of electric meters, clocks, and watches. It is used to make photocells and delay-lines for electronic circuits.
Cesium has industrial uses in lamps and radio emission. It is also used in chemical vapor deposition to produce thin films of various materials. Caesium is also used to dope semi-conductors and as an additive to thin films of gallium arsenide to form electron emitters in cathode ray tubes.
The applications of caesium in nuclear reactors are mainly as a moderator and control material. Caesium also has uses in the medical field; for example, it can be used to irradiate tumor cells. Caesium-137 is a radioactive isotope of cesium used in food irradiation and in cancer treatment.
Caesium is an essential element for some marine organisms and terrestrial animals, but it is toxic to humans at certain concentrations. The element is rapidly absorbed and accumulates in humans, leading to cardiovascular and neurological disorders. Ingested caesium can be removed from the body by chelation therapy and other detoxification methods.
In conclusion, caesium is a silvery-gold alkali metal element found on the periodic table of elements. It has a wide range of industrial and medical applications and is therefore crucial to many industries and medical treatments. However, its high reactivity and toxicity make it a hazard to humans and the environment if an excessive amount is released.
