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MHT CET Medical202625 April 2026Morning ShiftChemistryStructure of AtomActual

Which of the following elements has an electronic configuration, [ Ar ] 4s^2 ?

Options

  1. ANa
  2. BMg
  3. CK
  4. DCa

Correct answer

D. Ca

Step-by-step solution

The atomic number of Argon ( Ar ) is 18 . The given electronic configuration is [ Ar ] 4s^2 . Total number of electrons = 18 + 2 = 20 . The element with atomic number 20 is Calcium ( Ca ). Answer: Ca

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