There are 2 isotopes of an element with atomic mass 'y' The atomic mass of heavier isotope is y+2 - Chemistry - Some Basic Concepts of Chemistry

Question

There are 2 isotopes of an element with atomic mass 'y' The atomic
mass of heavier isotope is y+2 and that of lighter one is
y-1calculate abunbence of lighter istope?

Tinku Jangra · Accepted Answer

Let the percentage of higher isotope = xSo, the percentage of lighter isotope = 1-xAtomic mass of the element=(Atomic mass of heavier isotope×abundance)+Atomic mass of lighter isotope×abundance)Atomic mass of element=yHeavier isotope of element=y+2Lighter isotope of element=y-1So, y=(y+2)×x+(y-1)×(1-x)y=xy+2x+y-xy-1+x3x=1x=13So, Abundance of heavier isotope = 13×100=33
33%Abundance of lighter isotope=23×100=66 67%

There are 2 isotopes of an element with atomic mass 'y' .The atomic mass of heavier isotope is y+2 and that of lighter one is y-1calculate abunbence of lighter istope?