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Structure of the Atom — Science STD 9 — Question

Rajasthan BoardEnglish MediumSTD 9ScienceStructure of the Atom1 Mark
Question
An atom with 3 protons and 4 neutrons will have a valency of:
✓

Answer

  1. 1
Explanation:
Atomic number = Number of protons = 3
Mass number = Number of protons + number of neutrons =3 + 4 = 7
Electronic configuration of the atom is 2, 1(K,L)
Hence, its valency is 1.

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