Tellurium-122 is a stable isotope. It is an isotope of Tellurium.[1] Tellurium is a Block P, Group 16, Period 5 element. The number of electrons in each of Tellurium's shells is 2, 8, 18, 18, 6 and its electronic configuration is [Kr] 4d10 5s2 5p4. In its elemental form tellurium's CAS number is 13494-80-9. The tellurium atom has a radius of 143.2.pm and it's Van der Waals radius is 206.pm. Tellurium is a p-type semiconductor, and shows greater conductivity in certain directions, depending on alignment of the atoms. It is grown in crystalline form with other elements such as indium telluride. Its conductivity increases slightly with exposure to light which makes many tellurides candidates for solar energyapplications. . Tellurium improves the machinability of copper and stainless steel, an