Question

two isotopes of element X in ratio 1 ratio 2 and mass is M and M+0.5 find the mean of their mass

Answer 1

$<b>$
Given,
Ratio of two Isotopes of Element X = 1:2

Mass of one Isotope of Element X = M
& Mass of other Isotope of Element X = M+0.5


We know,
Mean Mass Number is the Average Mass of all Isotopes

Mean Mass Number :
$\implies \frac{(1×M)+ (2× (M+0.5))}{1+2}$

$\implies \frac{3M+1}{3}$


Therefore,
Mean Mass Number = $M+\frac{1}{3}$