Define electron valency and it types of exit with example
Answers
● A valence electron is an outer shell electron that is associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
Answer:
The combining capacity of an atom is known as its valency. The number of bonds that an atom can form as part of a compound is expressed by the valency of the element.
We all know how electrons in an atom are arranged in shells/orbitals. Valence electrons are those electrons which are present in the outermost orbit of the atom. From the Bohr-bury scheme, we can say that the outermost shell can contain a maximum of 8 electrons. Only a little chemical activity is observed when the outermost shell is completely filled. We can also say that it’s combining capacity becomes zero.
For example, nitrogen forms a number of compounds with hydrogen such as NH3, N2H4, N3H in which nitrogen atoms have valencies of 3, 2 and 1/3 respectively. Thus, this concept of valency as a mere number was not clear. Therefore, later on valency was defined as the number of chemical bonds formed by an atom in a molecule
Noble gases have a completely filled outermost shell and that’s why they are least reactive. Other element’s reactivity depends upon their ability to attain the noble gas configuration. In this section, we shall learn more about the valency of an atom.
Valence Electrons
If the outermost shell has 8 electrons then the element is said to have a complete octet. By gaining, sharing and losing the electrons the atoms complete their outermost orbital and make an octet.
The capacity of an atom is described by the total number of electrons lost, gained or shared to complete its octet and it also determines the valency of the atom.
Explanation:
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