Question

Equivalent weight of aluminium in $ A{l_2}{O_3} $ is-

Answer 1

Hint: The molecular weight of the solute divided by the valence of the solute gives the equivalent weight of a solution. In an acid-base analysis like titration, equivalent weight is used to determine the mass of a chemical that reacts with one atom of hydrogen.
 $ Equivalent{\text{ weight = }}\dfrac{{Molecular{\text{ weight}}}}{{Valency}} $

Complete answer:
As we know, the valency of $ Al $ in $ A{l_2}{O_3} $ is $ 3 $ .
Molecular weight of $ A{l_2}{O_3} $ is $ 27 $ .
By using the above formula, we can calculate the equivalent weight,
 $ Equivalent{\text{ weight = }}\dfrac{{Molecular{\text{ weight}}}}{{Valency}} $
Substituting the values in the above formula,
Equivalent weight $ = \dfrac{{27}}{3} $
Equivalent weight $ \Rightarrow 9 $
Hence, the equivalent weight of aluminium in $ A{l_2}{O_3} $ is $ 9 $ .

Additional Information:
Aluminium oxide, also known as $ A{l_2}{O_3} $ , is an inorganic chemical reagent. Alpha-Alumina is also known as alumina, alundum, or alkoxide. It is found in the form of corundum, rubies, sapphires, and emeralds in nature. It's an amphoteric chemical that reacts with acids as well as bases. It is white and appears as a solid. It has no odour and is water insoluble. The crystalline form of this chemical, known as -aluminium oxide or corundum, is the most prevalent. It is widely used and suitable for use as an abrasive and in cutting tools due to its hardness.

Note:
Valency is known as the combining capacity of the atom and atomic weight is the weighted average of all the masses of the naturally occurring isotopes of a chemical element. The unit of equivalent weight is an atomic mass unit.