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2. structure of atom — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistry2. structure of atom1 Mark
MCQ
Atomic number of elements represent
  • ✓
    Number of protons in the nucleus
  • B
    Number of neutrons in the nucleus
  • C
    Number of protons and neutrons in nucleus
  • D
    The valency of an element
✓

Answer

Correct option: A.
Number of protons in the nucleus
a
Atomic number of an element represents the number of protons in the nucleus. It is also equal to the number of electrons in neutral atom. The number of neutrons is equal to the difference between mass number and atomic number.

For example, for ${ }_{17}^{37} Cl$, the atomic number is $17$, the mass number is $37$ , there are $17$ , electrons, $17$ protons and $37-17=20$ neutrons.

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