The valency of an element is the combining capacity of that element. The valency of an element is determined by the number of valence electrons present in the atom of that element.If the number of valence electrons of the atom of an element is less than or equal to four, then the valency of that element is equal to the number of valence electrons. For example, the atom of silicon has four valence electrons and so, it has valency equal to four.On the other hand, if the number of the number of valence electrons of the atom of an element is greater than 4, then the valency of that element is obtained by subtracting the number of valence electrons from 8. For example, the atom of oxygen has 6 valence electrons. and so, the valency of oxygen is (8 – 6) 2.

Valency:- The minimum no.of electron which is gain, loss or shared by any elements to complete it's octate or duplate....eg:- Oxygen:- It will gain 2electron to complete it's octate.... Silicon :- It will share 4 electrons to complete it's octate....

Valency

Valency is a term used in chemistry to describe the combining capacity of an element. It refers to the number of electrons an atom of an element can gain, lose, or share in order to achieve a stable electron configuration and form chemical bonds with other atoms. Valency is determined by the number of valence electrons an atom possesses.

Valency of Silicon

Silicon is an element with atomic number 14. It belongs to Group 14 in the periodic table, which means it has four valence electrons. These valence electrons are found in the outermost energy level of the silicon atom, known as the valence shell. Silicon has an electron configuration of 1s2 2s2 2p6 3s2 3p2, where the outermost shell contains four electrons.

The valency of silicon can be determined by the number of electrons it needs to gain, lose, or share to achieve a stable electron configuration. Since silicon has four valence electrons and its valence shell can accommodate a total of eight electrons, it tends to gain or share four more electrons to complete its octet.

Hence, the valency of silicon is four, as it requires four more electrons to achieve a stable configuration.

Valency of Oxygen

Oxygen is an element with atomic number 8. It belongs to Group 16 in the periodic table, which means it has six valence electrons. The electron configuration of oxygen is 1s2 2s2 2p4, where the outermost shell contains six electrons.

Similar to silicon, the valency of oxygen can be determined by the number of electrons it needs to gain, lose, or share to achieve a stable electron configuration. Oxygen requires two more electrons to complete its octet, as its valence shell can accommodate a total of eight electrons.

Hence, the valency of oxygen is two, as it needs two more electrons to achieve a stable configuration.

Summary

- Valency refers to the combining capacity of an element and is determined by the number of valence electrons an atom possesses.
- Silicon has four valence electrons and requires four more electrons to achieve stability, resulting in a valency of four.
- Oxygen has six valence electrons and requires two more electrons to achieve stability, resulting in a valency of two.