Question

Select the pairs of isotopes and isotoes form the following nuclei:
`._11Na^(22)`,`._12Mg^(24)`,`._11Na^(24)`,`._10Ne^(23)`

Answer 1

(a) `._11Na^(22)` and `._11Na^(24)` are isotopes as both have the same charge number (Z=11) , but different mass number `(A=22,24)`.
(b) `._11Na^(24)` and `._10Ne^(23)` are isotones, because both contain the same number of neutrons `(=24-11=13 and 23-10=13)`.