Question

Use the periodic table to determine which of the following could be an isotope of indium (In). Check all that apply. Z = 49, A = 113 N = 64, Z = 49 N = 61, A = 113 A = 110, N = 49

Answer 1

The isotopes are the elements with same atomic number but different atomic mass or mass number

The mass number is denoted by Z

The mass number is denoted by A

The number of neutrons = N

We know that for an element

A = Z + N

As given the element is indium , its atomic number = Z = 49

Z = 49, A = 113 N = 64,  This could be an isotope of indium

Z = 49 N = 61, A = 113 , this could also be an isotope of indium

A = 110, N = 49 it means Z = Z - N = 110-49 = 61 So this is not isotope of indium

Answer 2

correct answer is Z = 49, A = 113

N = 64, Z = 49 so A&B