Question

What is the chemical formula of Aluminium hydroxide?

• A. $Al(OH{)}_2$
• B. $Al(OH{)}_3$
• C. $A{l}_2(OH{)}_3$
• D. $A{l}_2\left(OH\right)$

Answer 1

Answer: (B)

$Al(OH{)}_3$

The valency of aluminium is $+3$ and that of $OH$ is $-1$ so on cross multiplying the valency we get $Al(OH{)}_3$.

As a mineral, it is naturally found as the ore called gibbsite. The molecular weight of aluminium hydroxide is 78.0 g/mol.

Hence, the correct option is $\text{B}$