Here are the essential concepts you must grasp in order to answer the question correctly.
Isotopes
Isotopes are variants of a particular chemical element that have the same number of protons (atomic number, Z) but different numbers of neutrons, resulting in different mass numbers (A). For example, carbon-12 and carbon-14 are isotopes of carbon, with 6 and 8 neutrons, respectively.
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Atomic Number (Z)
The atomic number (Z) is the number of protons in the nucleus of an atom, which defines the element and its position in the periodic table. It determines the chemical properties of the element and its identity; for instance, an element with Z = 27 is cobalt.
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Mass Number (A)
The mass number (A) is the total number of protons and neutrons in an atom's nucleus. It is used to distinguish between different isotopes of the same element. For example, if an element has Z = 27 and A = 60, it has 27 protons and 33 neutrons (60 - 27 = 33).
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