Roasting of sulphide ore gives the gas (A).(A) is a colourless gas. Aqueous solution of (A) is acidic. The gas (A) is______.

(a)

CO₂

(b)

SO₃

(c)

SO₂

(d)

H₂S

Which of the following statements, about the advantage of roasting of sulphide ore before reduction is not true?

(a)

\(\Delta { G }_{ f }^{ 0 }\) of sulphide is greater than those for CS₂ and H₂S

(b)

\(\Delta { G }_{ r }^{ 0 }\) is negative for roasting of sulphide ore to oxide

(c)

Roasting of the sulphide to its oxide is thermodynamically feasible

(d)

Carbon and hydrogen are suitable reducing agents for metal sulphides

Wolframite ore is separated from tinstone by the process of________.

(a)

Smelting

(b)

Calcination

(c)

Roasting

(d)

Electromagnetic separation

Electrochemical process is used to extract_______.

(a)

Iron

(b)

Lead

(c)

Sodium

(d)

silver

Which one of the following ores is best concentrated by froth – floatation method?

(a)

Magnetite

(b)

Haematite

(c)

Galena

(d)

Cassiterite

Zinc is obtained from ZnO by________.

(a)

Carbon reduction

(b)

Reduction using silver

(c)

Electrochemical process

(d)

Acid leaching

The following set of reactions are used in refining Zirconium 
\(Zr \text{(impure)}+2I_{ 2 }\overset { 523k }{ \longrightarrow } ZrI_{ 4 }\)
\({ ZrI }_{ 4 }\overset { 1800K }{ \longrightarrow } Zr \text{(pure)}+{ 2I }_{ 2 }\)This method is known as ______.

(a)

Liquation

(b)

Van Arkel process

(c)

Zone refining

(d)

Mond’s process

The incorrect statement among the following is______.

(a)

Nickel is refined by Mond’s process

(b)

Titanium is refined by Van Arkel’s process

(c)

Zinc blende is concentrated by froth floatation

(d)

In the metallurgy of gold, the metal is leached with dilute sodium chloride solution

Which of the following reduction is not thermodynamically feasible?

(a)

\({ Cr }_{ 2 }{ O }_{ 3 }+2Al\longrightarrow { Al }_{ 2 }{ O }_{ 3 }+2Cr\)

(b)

\(\mathrm{Al}_2 \mathrm{O}_3+2 \mathrm{Cr} \longrightarrow \mathrm{Cr}_2 \mathrm{O}_3+2 \mathrm{Al}\)

(c)

\(3Ti{ O }_{ 2 }+4Al\longrightarrow 2A{ l }_{ 2 }{ O }_{ 3 }+3Ti\)

(d)

none of these

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)

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

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

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

(a)

Wrought iron > Pig iron > castiron

(b)

Castiron > 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

Pick out the alloy that contains a non-metal as a constituent in it ________.

(a)

Brass

(b)

Bronze

(c)

Steel

(d)

Invar

In acid leaching process the insoluble sulphide is converted into soluble sulphate and elemental_______.

(a)

carbon

(b)

lead

(c)

sulphur

(d)

zinc

Na[Ag(CN)₂] is _________.

(a)

Sodium aurocyanide

(b)

Sodium meta aluminate

(c)

Aluminosilicate

(d)

Sodium dicyano argentate

A mixture containing sulphides of copper and iron is called______

(a)

mineral

(b)

ore

(c)

matte

(d)

matrix

Sodium cyanide solution is used to extract _________from its ores

(a)

copper

(b)

silver

(c)

gold

(d)

both (b) and (c)

In Hall-Heroult process___________act as an anode.

(a)

Carbon blocks

(b)

hydrogen

(c)

copper rods

(d)

Zinc rods