A different atom of iodine has a mass number of 128. What is this atoms relationship to the atom with a mass of 126

The answer is below

Explanation:

They are isotopes. Isotopes are molecules that have the same atomic number but have different atomic mass because the number of neutrons is different.

Iodine has an atomic mass of 126 g and its atomic number is 53.

# of neutrons = 126 - 53 = 73

Its isotope has an atomic mass of 128 g its atomic number is also 53, but the number of neutrons is different.

# neutrons = 128 - 53 = 75