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QJEEM04Ch0cf2: JEE Main 2004 Chemistry - Class 11 JEEM04Ch0cf2 Solution: Which one of the following sets of ions represents the…

Which one of the following sets of ions represents the collection of isoelectronic species? (Atomic nos. : F = 9, Cl = 17, Na = 11, Mg = 12, Al = 13, K = 19, Ca = 20, Sc = 21)

Multiple Choice Options

  • A K+, Cl-, Mg2+, Sc3+
  • B Na+, Ca2+, Sc3+, F-
  • C K+, Ca2+, Sc3+, Cl-
  • D Na+, Mg2+, Al3+, Cl-

Step-by-Step Verified Solution

Isoelectronic means those species whose no of electrons are same.

Ions Atomic No No of Electron
K+ 19 19-1=18
Ca+2 20 20-2=18
Sc+3 21 21-3=18
Cl- 17 17+1=18


So, option (C)(C) is correct.

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