Which of the following is not a mineral of aluminium?

(a)

Bauxite

(b)

Cryolite

(c)

China clay

(d)

Malachite

Among the following, one does not belong to calcination, Pick the odd one out.

(a)

\({ PBCO }_{ 3 }\overset { \Delta }{ \longrightarrow } PBO+{ CO }_{ 2 }\uparrow \)

(b)

\({ CaCo }_{ 3 }\overset { \Delta }{ \longrightarrow } Cao+{ CO }_{ 2 }\uparrow \)

(c)

\(PbS{ O }_{ 3 }\overset { \Delta }{ \rightarrow } PbO+{ 2SO }_{ 2 }\uparrow \)

(d)

\({ ZnCO }_{ 3 }\overset { \Delta }{ \rightarrow } ZnO+{ CO }_{ 2 }\uparrow \)

Name the process by which elements such as germanium, silicon and gallium are refined.

(a)

Vapour phase method

(b)

Electrolytic refining

(c)

Zone refining

(d)

Van-Arkel method

In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with________.

(a)

Iron sulphide (FeS)

(b)

Carbon monoxide (CO)

(c)

Copper (I) sulphide (Cu₂S)

(d)

Sulphur dioxide (SO₂)

Which one of the following element is present as a impurity in pig iron?

(a)

Phosphorus

(b)

Manganese

(c)

Carbon

(d)

Silicon