Bauxite has the composition ______.

(a)

Al₂O₃

(b)

Al₂O₃.nH₂O

(c)

Fe₂O₃.2H₂O

(d)

None of these

Which of the metal is extracted by Hall-Heroult process?

(a)

Al

(b)

Ni

(c)

Cu

(d)

Zn

Electrochemical process is used to extract_______.

(a)

Iron

(b)

Lead

(c)

Sodium

(d)

silver

Zinc is obtained from ZnO by________.

(a)

Carbon reduction

(b)

Reduction using silver

(c)

Electrochemical process

(d)

Acid leaching

Which of the following is used for concentrating ore in metallurgy?

(a)

Leaching

(b)

Roasting

(c)

Froth floatation

(d)

Both (a) and (c)

Which of the following is not true with respect to Ellingham diagram?

(a)

Free energy changes follow a straight line. Deviation occurs when there is a phase change.

(b)

The graph for the formation of CO₂ is a straight line almost parallel to free energy axis.

(c)

Negative slope of CO shows that it becomes more stable with increase in temperature.

(d)

Positive slope of metal oxides shows that their stabilities decrease with increase in temperature.

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)

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

Which of the following mineral contains calcium as well as magnesium?

(a)

Zinc blende

(b)

Aragonite

(c)

Dolomite

(d)

Carnallite

Identify the decreasing order of carbon content in different forms of iron________.

(a)

Wrought iron > Pig iron > cast iron

(b)

Cast iron > Pig iron > Wrought iron

(c)

Pig iron > Cast iron > Wrought iron

(d)

Cast iron > Wrought iron > Pig iron

The process of heating of copper pyrites to remove sulphur is called ________.

(a)

froth flotation

(b)

roasting

(c)

calcination

(d)

smelling

Na[Ag(CN)₂] is _________.

(a)

Sodium aurocyanide

(b)

Sodium meta aluminate

(c)

Aluminosilicate

(d)

Sodium dicyanoargentate

Semiconductors are purified by_______ method.

(a)

Zone refining

(b)

Electrolytic refining

(c)

Mond's process

(d)

Bessemerisation

In the metallurgy of iron, limestone is added to coke. Which acts as a_______

(a)

Reducing agent

(b)

Oxidising agent

(c)

Slag

(d)

Flux

A mixture containing sulphides of copper and iron is called______

(a)

mineral

(b)

ore

(c)

matte

(d)

matrix

In Hall-Heroult process ___________act as an anode.

(a)

Carbon blocks

(b)

hydrogen

(c)

copper rods

(d)

Zinc rods

Malachite

(1)

Nickel

Cuprite

(2)

CuCO₃CU(OH)₂

Azurite

(3)

Anglesite

Cerussite

(4)

Haematite

Gravity separation

(5)

Tin

Froth floatation

(6)

Zinc Blende

Sulphate ore

(7)

Pb

Liquation

(8)

Cu₂O

Mond's process

(9)

Cu

Electrolytic refining

(10)

Copper