The most common isotope of chromium has a mass number of 52. which notation represents a different isotope of chromium?
a. 52/24cr
b. 54/24cr
c. 24/52cr
d. 24/54cr

Each element symbol has two basic numbers, atomic number and mass. Atomic number, a number in a lower position states the number of protons, which is typical of each element and is unchangeable. Mass number, placed in the upper position, is a total of protons and Neutrons, and is changeable due to difference in Neutrons in the isotopes. Thus, a different isotope of chromium must have the same protons (atomic number), but a different mass number.

Well the best answer would be option B. 54/24Cr