Composition of the nuclei of two atomic species, X and Y, are given as under X Y Protons = 6 6 Neutrons = 6 8 Give the mass numbers of X and Y. What is the relation between the two species?
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Solution:
Mass number of X: Protons + neutrons = 6+6 = 12
Mass number of Y: Protons + neutrons = 6+8 = 14
They are the same element, and their atomic numbers are the same.
They are isotopes, as they differ in the number of neutrons and hence their mass numbers.
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