The percentage of carbon in high carbon steel is_________.

(a)

0.5 - 1%

(b)

0.15 - 1.5%

(c)

0.15 - 1.5%

(d)

0.15 - 0.3%

Steel is an alloy of___________

(a)

iron and carbon

(b)

iron and calcium

(c)

copper and carbon

(d)

copper and iron

Sodium cyanide solution is used to extract _________from its ores

(a)

copper

(b)

silver

(c)

gold

(d)

both (b) and (c)

Galena is_______.

(a)

PbS

(b)

ZnS

(c)

Ag₂S

(d)

FeS₂

In Hall-Heroult process ___________act as an anode.

(a)

Carbon blocks

(b)

hydrogen

(c)

copper rods

(d)

Zinc rods