The valency of aluminium in Al₂O₃ is: MCQ with Answer and Explanation

The valency of aluminium in Al₂O₃ is:
A. 2
B. 4
C. 3
D. 1
Answer: Option C
Solution (By JKExamLibrary)
Aluminium oxide: Al³⁺ and O²⁻. To balance charges, 2 Al³⁺ (total +6) combine with 3 O²⁻ (total -6). Thus valency of Al is 3. It loses three electrons. Formula determined by criss-cross method.

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