Question

The common impurity present in bauxite is:
A.CuO
B.ZnO
C.$F{e_2}{O_3}$
D.$C{r_2}{O_3}$

Answer 1

Hint: Bauxite is a metallic mineral though it is also used as an industrial mineral. It is the only ore used for large scale aluminium production. The major impurities are iron oxides, silicon dioxides, clay mineral kaolinite as well as small amounts of $Ti{O_2}$.

Complete step by step answer:
Bauxite ore is soft and red clay, rich in alumina. However, it is a form of sedimentary rock and is the principal source of the popular metal aluminium. Moreover, this mineral is generally obtained from topsoil in various tropical and subtropical regions. The ore is acquired through mining operations.
Now, the major impurities in Bauxite are iron oxides (goethite and hematite). Silicon dioxide, the clay mineral kaolinite as well as small amounts of anatase ($Ti{O_2}$). Hence, among the given options the major impurity is $F{e_2}{O_3}$.
So, when iron oxide is the chief impurity then the ore is red bauxite and when silica is the chief impurity then the ore is white bauxite.

Hence, option C is correct.

Note:
Some common uses of bauxite are in metallurgy, in industries, in building material and road aggregates etc. It has limited uses but has wide applications in paper making, water purifying and petroleum refining. Additionally, it is also used in other sectors like rubber, plastic, paints and cosmetics.