How will you find the valency of chlorine, Sulphur and magnesium?

Here’s how we find the valency of chlorine (Cl), sulfur (S), and magnesium (Mg):
Chlorine (Cl):
– Chlorine belongs to Group 17 (or Group VIIA) of the periodic table.
– It has 7 electrons in its outer shell (2s² 2p⁶ 3s² 3p⁵).
– To achieve a stable electron configuration like the noble gas neon (with 8 electrons in its outer shell), chlorine tends to gain 1 electron.
– Therefore, the valency of chlorine is -1.

Sulfur (S):
– Sulfur is in Group 16 (or Group VIA) of the periodic table.
– It has 6 electrons in its outer shell (2s² 2p⁶ 3s² 3p⁴).
– Sulfur needs 2 more electrons to achieve a stable electron configuration, similar to the noble gas argon (with 8 electrons in its outer shell).
– Thus, the valency of sulfur is -2.

Magnesium (Mg):
– Magnesium belongs to Group 2 (or Group IIA) of the periodic table.
– It has 2 electrons in its outer shell (3s²).
– Magnesium tends to lose these 2 electrons to achieve a stable electron configuration, akin to the noble gas neon (with 8 electrons in its outer shell).
– Hence, the valency of magnesium is +2.

Valency signifies the combining capacity of an element based on its ability to gain, lose, or share electrons to attain a stable configuration. This understanding helps predict how elements interact and form compounds during chemical reactions.