Which of the following represents a pair of isotopes?
Atomic Number
Mass Number
A)I 17 34 II 18 34
B)I 7 14 II 8 14
C)I 17 35 II 17 37
D)I 17 37 II 18 38
E)I 7 15 II 8 16

Question

Quizplus · Accepted Answer

Isotopes have the same atomic number (number of protons) but different mass numbers (sum of protons and neutrons). In option C, both isotopes have the same atomic number of 17 but different mass numbers of 35 and 37, indicating that they have different numbers of neutrons. The other options either have different atomic numbers (options B and E) or the same atomic and mass numbers (options A and D), indicating that they are not isotopes.

Which of the Following Represents a Pair of Isotopes