Question

what are ISOELECTRONIC SPECIES and give examples.

Answer 1

Isoelectronic species refers to the species which have same number of electrons. For e.g. CO and N2 are isoelectronic as both have same number of electrons i.e. 14. Hope it’s clear…

Answer 2

Answer: Isoelectronic molecules are defined as the molecules which have the same electronic structure and have the same number of valence electrons.

In the calculation, the positive charge is subtracted from the total number of  electrons and negative charge is added to the total number of electrons.

Calculating the number of valence electrons for each molecule:

1. For $Mg^{2+$

Electrons of magnesium are 12 , and on losing 2 electrons the electrons are 10.

$[Mg]:12:1s^22s^22p^63s^2$

$[Mg^{2+}]:1:1s^22s^22p^63s^0$

2. For $F^-$

Electrons of fluorine are 9 , and on gaining 1 electron the electrons are 10.

$[F]:9:1s^22s^22p^5$

$[F^-]10:1s^22s^22p^63s^23p^6$

2. For $Ne$

Electrons of neon are 10.

$[Ne]:10:1s^22s^22p^6$

As, the total number of electrons of $Mg^{2+}$, $F^-$ and $Ne$ are same. Thus, they are considered as isoelectronic species.