Question

Are Na and K valence- Isoelectronic species??​

Answer 1

The K+ ion is isoelectronic with the Ca2+ ion. The carbon monoxide molecule (CO) is isoelectronicto nitrogen gas (N2) and NO+.

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More Examples of Isoelectronic Ions and Elements.

Answer 2

Hey Mate!

Na ( Sodium) belongs to 1st group and 3rd period of the periodic table

K (Potassium) too belongs to 1st group but 4th period of the periodic table .

Now for your convenience Here is a trick

For elements belonging to same group the

NO. OF 'VALENCE ELECTRONS'  IS SAME

But this condition only holds for elements of same group

For elements of same period The no. of shells remains same

Now to answer your question

Since Na and K belong to 1st group ( alkali metals)

They have same no. of valence electrons

NOTE :-

Isoelectronic species are those elements

( charged) which have same no. of protons

But Na and K do not have same no. of Protons

As

Na has atomic no. of 11 i.e, protons =11

K has atomic no. of 19 i.e, protons=19

Hence are not isoelectronic species

but do have same no. of valence electrons