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QJEEM03Ch17c7: JEE Main 2003 Chemistry - Class 11 JEEM03Ch17c7 Solution: Which one of the following groupings represents a collection of …

Which one of the following groupings represents a collection of isoelectronic species? (At. nos. : Cs : 55, Br : 35)

Multiple Choice Options

  • A N3-, F-, Na+
  • B Be, Al3+, Cl-
  • C Ca2+, Cs+, Br
  • D Na+, Ca2+, Mg2+

Step-by-Step Verified Solution

Isoelectronic means those species whose electron number are same.

Species Atomic Number Electron Number
N3- 7 7 + 3 = 10
F- 9 9 + 1 = 10
Na+ 11 11 - 1 = 10
Be 4 4
Al3+ 13 13 - 3 = 10
Cl- 17 17 + 1 = 8
Ca2+ 20 20 - 2 = 18
Cs+ 55 55 - 1 = 54
Br 35 35
Mg2+ 12 12 -2 = 10

∴\therefore N3-, F-, Na+

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