Question

Different between valency and valence electrons

Answer 1

Answer:-

Valence electrons:

• Valence electrons are the electrons which are located in the outermost or last shell of an element.

For example,

Let us take an element sodium (Na) .

It's atomic number (Z) is 11.

It's Configuration is 1s² 2s² 2p⁶ 3s¹.

The last shell (n) is 3.

Number of electrons in 3rd shell is 1.

Hence, the number of Valence electrons in sodium = 1.

Valency:

• The combining capacity of an element is called it's valency.

(or)

• It is defined as the number of electrons that are lost or gained or shared with one atom of an element, to acquire the noble gas configuration (ns² np⁶) or to attain stability.

• Valency of an element can be found by the number of Valence electrons of an element.

• If the number of Valence electrons in an element are less than 4 then , their valency is equal to the number of valence electrons.

• And, if the Valence electrons are greater than 4 , then their valency = 8 - no. of valence electrons.