Question

Common impurities present in bauxite are

• A. $\mathrm{CuO}$
• B. $\mathrm{ZnO}$
• C. $\mathrm{CaO}$
• D. ${\mathrm{SiO}}_2$

Answer 1

The correct option is D

${\mathrm{SiO}}_2$

Explanation of the correct answer:

The correct answer is option D:

• Although it is also utilised as an industrial material, bauxite is predominantly a metallic mineral.
• It is the sole mineral utilised in the large-scale manufacture of aluminium.
• Aluminium ore is bauxite (${\mathrm{Al}}_2{\mathrm{O}}_3$).
• The bauxite is refined to produce aluminium oxide, a white powder form from which aluminium may be recovered.
• Bauxite deposits are mostly created by aluminous rock weathering; while some have been transported to their current locations, the majority are residual accumulations from which the majority of the other parent rock constituents, except alumina, have been leached.
• Bauxite contains a variety of iron oxides, including hematite and goethite, ${\mathrm{Fe}}_2{\mathrm{O}}_3$, silicon dioxide from sand, ${\mathrm{SiO}}_2$, Kaolinite, and a trace amount of ${\mathrm{TiO}}_2$.

Explanation of the incorrect answers:

Options A, B, and C:

1. The impurities present in Bauxite do not include$\mathrm{CuO}$, $\mathrm{ZnO}$, and $\mathrm{CaO}$.
2. Thus, these options are incorrect.

Hence, option D is correct, i.e., ${\mathrm{SiO}}_2$.