Valency
* Valency refers to the combining capacity of an atom or ion. It's a general term that describes how many bonds an atom can form.
* Both sodium (Na) and chlorine (Cl) have a valency of 1. This means they can form one single bond with another atom.
Electrovalency
* Electrovalency is the number of electrons an atom gains or loses to form an ion. It's specific to ionic bonding.
* Sodium (Na) has an electrovalency of +1 because it loses one electron to become a positively charged ion (Na+).
* Chlorine (Cl) has an electrovalency of -1 because it gains one electron to become a negatively charged ion (Cl-).
Why the Difference?
The difference in electrovalency arises from the different ways sodium and chlorine achieve a stable electron configuration:
* Sodium: Sodium has one electron in its outermost shell. By losing this electron, it achieves a stable configuration with a full outer shell (like the noble gas neon).
* Chlorine: Chlorine has seven electrons in its outermost shell. By gaining one electron, it also achieves a stable configuration with a full outer shell (like the noble gas argon).
In summary:
* Both sodium and chlorine have a valency of 1, meaning they can form one bond.
* Sodium loses an electron to become Na+ (electrovalency +1).
* Chlorine gains an electron to become Cl- (electrovalency -1).
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