Answer: The atomic number indicates the number of protons within the core of an atom. The atomic number is an important concept of chemistry and quantum mechanics. An element and its place within the periodic table are derived from this concept. ... These electrons mainly determine the chemical behaviour of an atom. The chemical properties of an element, are determined by the number of protons in the nucleus. This number of protons is called the atomic number. The mass of the atom, its atomic mass, depends upon the sum of the number of protons and the number of neutrons present in the nucleus.
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