The atomic number (Z) of an element is equal to the:
ANumber of neutrons inside the central nucleus
BSum of protons and neutrons in the nucleus
CNumber of electron shells in a neutral atom
DNumber of protons inside the central nucleus
Answer & Solution
Correct answer: D. Number of protons inside the central nucleus
The atomic number Z is defined as the number of protons in the nucleus. In a neutral atom, it also equals the number of electrons. Z defines the element uniquely.
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