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Structure of Atom — Chemistry STD 11 Science — Question

Maharashtra BoardEnglish MediumSTD 11 ScienceChemistryStructure of Atom3 Marks
Question
Explain: Atomic mass number.
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Answer

  • The sum of the total number of protons and neutrons present in the nucleus of an atom is called the atomic mass number of that atom.
  • Atomic mass number is represented by A
  • Mass number (A) = Number of protons (Z) + Number of neutrons (N) = Total number of nucleons
    ∴ A = Z + N OR N = A – Z

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