Physics Ncert Solutions Class 12th Nuclei Class 12th Physics

13.23 In a periodic table the average atomic mass of magnesium is given as 24.312 u. The average value is based on their relative natural abundance on earth. The three isotopes and their masses are ${}_{12}^{24}{M g}$ (23.98504u), ${}_{12}^{25}{M g}$

(24.98584u) and ${}_{12}^{26}{M g}$ (25.98259u). The natural abundance of ${}_{12}^{24}{M g}$ is 78.99% by mass. Calculate the abundances of other two isotopes.

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Payal Gupta | Contributor-Level 10

7 months ago

13.23 Average atomic mass of magnesium, m = 24.312 u

Mass of magnesium isotope ${}_{12}^{24}{M g}$ , $m_{1}$ = 23.98504u

Mass of magnesium isotope ${}_{12}^{25}{M g}$ , $m_{2}$ = 24.98584u

Mass of magnesium isotope ${}_{12}^{26}{M g}$ , $m_{3}$ = 25.98259u

Let the abundance of magnesium isotope ${}_{12}^{24}{M g}$ be $η_{1}$ = 78.99 %

Let the abundance of magnesium isotope ${}_{12}^{25}{M g}$ be $η_{2}$ = x %

Therefore, the abundance o

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Physics Ncert Solutions Class 12th 2023

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