The chemical formula of diaspora, an ore of aluminum, is:
(A) Al2O3.3H2O
(B) Al2O3.2H2O
(C) Al2O3.H2O
(D) Al2O3

To solve the question about the chemical formula of diaspora, an ore of aluminum, let's analyze the options given.

Diaspore is a mineral form of aluminum oxide (Al₂O₃) with water molecules associated with it, making it a hydrate. Here’s the breakdown of the options provided:

(A) Al₂O₃·3H₂O: This formula indicates that three water molecules are associated with one formula unit of aluminum oxide. This compound is known as gibbsite, not diaspore.

(B) Al₂O₃·2H₂O: This indicates that two water molecules are associated with one formula unit of aluminum oxide. This formula represents bauxite, which is not the correct answer for diaspore.

(C) Al₂O₃·H₂O: This indicates that one water molecule is associated with one formula unit of aluminum oxide. This formula corresponds to diaspore, which is a hydrate of aluminum oxide.

(D) Al₂O₃: This formula represents pure aluminum oxide with no water molecules associated. This is not diaspore.