which of the following is isoelectronic a) Fe3+,Co3+ b) Fe3+,Mn2+c) Co3+,Sc3+d) Sc3+,Ti3+
The correct option is B.
Isoelectronic species are those species which have equal no of electrons.
Fe has 26 electrons and for Mn has 25 electron
therefore,
Fe 3+ is formed by loss of 3 electrons hence it contain 23 electrons
Mn undergoes loss of 2 electrons to form Mn2+ therefore it contain 23 electrons
Since number of electrons are same for both species therefore both are Isoelectronic.