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KVPY2012ChemistryStructure of Atom

The number of electrons plus neutrons in ₁₉⁴⁰ ~K ⁺ is -

Options

  1. A38
  2. B59
  3. C39
  4. D40

Correct answer

C. 39

Step-by-step solution

array ll ₁₉⁰ ~K ⁺ & Neutrons =21, Electron =18, & 21+18=39 array

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