Valency of Metal M in the 13th Group of the Modern Periodic Table

The valency of an element is a measure of its combining capacity with other elements to form chemical compounds. It represents the number of electrons an atom of the element can gain, lose, or share to achieve a stable electron configuration.

Understanding the 13th Group of the Modern Periodic Table
The modern periodic table is divided into several groups or families based on similar chemical properties. Group 13 is known as the boron group, and it includes elements such as boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl). These elements have three valence electrons in their outermost energy level.

Valency of Group 13 Elements
The valency of elements in Group 13 is generally three. This is because they have three electrons in their outermost energy level. These valence electrons can be lost or shared to form compounds.

Formation of Compounds by Group 13 Elements
Group 13 elements tend to lose their three valence electrons to achieve a stable electron configuration. By losing these electrons, they form +3 cations. For example, aluminum readily loses its three valence electrons to form Al3+ ions.

Alternatively, Group 13 elements can also share their three valence electrons to form covalent compounds. In these compounds, the elements share their electrons with other non-metal elements to achieve a stable configuration. For instance, aluminum can form compounds such as AlCl3 by sharing its three valence electrons with three chlorine atoms.

Conclusion
In conclusion, the metal M belonging to the 13th group of the modern periodic table will have a valency of 3. This is because elements in Group 13 have three valence electrons, which they can either lose or share to achieve a stable electron configuration. The valency of 3 indicates that the metal M can either lose three electrons to form a +3 cation or share its three valence electrons to form covalent compounds.

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