Question

How many valence electrons does cadmium have?

Answer 1

Hint: To find the number of valence electrons in a cadmium atom , you should first know what is the atomic number of cadmium and then, by using that you can find the valence electrons present in the cadmium atom. Now you can easily answer the statement.

Complete answer:
- Cadmium is a metal which comes under the category of the transition elements and belongs to the d-block elements of the periodic table. Transition metals are those elements which come in between the s-block elements and p-block elements.
- It lies in the $12^{th}$ group and $5^{th}$ period of the periodic table.
- It has the atomic number as 48 and the mass number as 114 and has the electronic configuration as: ${{[Kr]}^{36}}4{{d}^{10}}5{{s}^{2}}$.
Now considering the statement as;
- The number of electrons present in an atom is always equal to the atomic number of that very element.
- And The electrons which are present in the outermost valence shell of an atom are called the valence electrons of the atom.
- From the electronic configuration of the cadmium atom, we come to know that the number of valence electrons present in the cadmium atom are two electrons ( i.e. in 5s orbital ).
Thus, the total number of electrons present in cadmium is two.

Note: Cadmium being a transition metal has ten electrons in its outermost shell and has a strong tendency to lose the electrons in 4s orbitals and thus, exhibits the oxidation state of +2 in their compounds.