Cesium

Cesium, Cs, chemical element with atomic weight 132.7. Belongs to Group II of alkali metals. In its properties, C. is very similar to the elements potassium and rubidium. C. was discovered in 1860 by Bunsen and Kirchhoff. In nature, it occurs in very small quantities together with potassium and lithium. Most frequently, lepidolite is used as a source of C., which occurs in our country in the largest deposits in Transbaikalia. C.-metal is white in color, melting point 28.45°, boiling point 670°, specific gravity 1.886 at 29° (liquid); at 20°--specific gravity 2.4 (metal solid); ignites in air. C. was attributed 'calming' properties, which is why it is mainly proposed in combination with bromine for nervous heart palpitations and epilepsy. No advantages over potassium and sodium salts have been found in C. salts. Preparations of C.: 1) bromide of C., colorless crystals, easily soluble in water; dose 0.25-2-3 times a day; 2) iodide of C. is used instead of potassium iodide in the same doses as the latter. In technology, C. salts are used in the preparation of luminous paints.