Q. 4.43 - An Introduction to General, Organic, and Biological Chemistry

Question

There are two naturally occurring isotopes of thallium:  ${}_{81}{}^{203}TI$ and ${}_{81}{}^{205}TI$. Use the atomic mass of thallium listed on the periodic table to identify the more abundant isotope.

Step-by-Step Solution

Answer

  ${}_{81}{}^{205}TI$  is more abundant isotope of thallium.

Step1 : Given information.

We have been given that,

${}_{81}{}^{203}TI , {}_{81}{}^{205}TI$

We need to find which isotope is more abundant in nature.

Step2 : Simplify.

${}_{81}{}^{205}TI$  is more abundant isotope of thallium as it comprises $70\%$ atomic mass of thallium whereas ${}_{81}{}^{203}TI$ isotope comprises only $30\%$ of the atomic mass .