The Soft Silvery Metallic Element :
Answer: (2) Cesium
The soft silvery metallic element which ionizes easily when haled or exposed to light and is presents in atomic clocks is Cesium.
The Cesium discovered by Robert Bunsen and Gustav Kirchhoff in 1860.
Some points about Cesium : –
Symbol = Cs
Atomic weight = 132.90
Atomic number = 55
Melting point = 28.5 degree celcius
Boiling point = 672 degree celcius
density = 1.93 g/cm cube
It is mostly used for cesium compound is as a drilling fluid. It is also used in the atomic clock and photoelectric cells.