Why thallium is not transition element?
Answers
Answer: Thallium is a chemical element with the symbol Tl and atomic number 81. It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. ... The +3 state resembles that of the other elements in group 13 (boron, aluminium, gallium, indium).
Explanation: The elements generally follow periodic trends except for certain Tl ... from the core and therefore are easier to remove; Tl does not fit this trend)* ... of these gems are due to transition metal impurities in their corondum structure.Thallium (Tl) with an atomic number of 81 is found in the periodic table with the symbol. Thallium is not freely found in nature. It is a soft grey post-transition metal .
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