Number of valence electrons present in an element (X) having atomic number 34 is
4
5
7
6

The number of valence electrons present in Ca atom

What is the number of valence electrons in the atom of an element A having atomic number 17 ? Name the valence shell of this atom.

What is the number of valence electrons in the atom of an element A having atomic number 20? Name the valence shell of this atom.

(a) What are valence electrons ? Where are valence electrons situated in an atom ? (b) What is the number of valence electrons in the atoms of an element having atomicm number 13 ? Name the valence shell of this atom.

Number of electrons present in the 3d sub-shell of an element having atomic number 37 is :

The number of valence electrons present in noble gases is:

Total number of d electrons present in an element with atomic number 78 is :-