Question

Mass numbers of two isotopes of an element differ by 2 units (A and A+2). Average atomic mass is 0.5 more than the lower mass number. What could be the ratio of the two isotopes?

Answer 1

Answer:

Explanation:

From the question it is clear that only two isotopes of the element exist in nature. Let us take their abundances to be x

Final Atomic Mass = (Abundance of 1st * Atomic Mass of 1st Isotopes) + (Abundance of 2nd * Atomic Mass of 2nd Isotopes)

A+0.5=(x∗A)/100+((100−x)∗(A+2))/100

100A+50=Ax+100A+200−Ax−2x

50=200−2x

2x=150

x=75

Hence isotope with atomic mass A has an abundance of 75% and that with (A+2) has 25%.

Answer 2

Answer:

Explanation:

The ratio of the two isotopes could be 75:25...