Page 201 - Chemistry ICSE Class X

Metallurgy 187
Extraction of Metals Based on their Position in the

Activity Series

Metals are extracted from the concentrated ore by a suitable method. The
method employed for extracting metal from its ore depends upon the
reactivity of the metal.
On the basis of reactivity, metals are grouped into the following
categories: A copper purification plant
ƒ Metals of very low reactivity.
ƒ Metals of low reactivity.

ƒ Metals of medium reactivity.
ƒ Metals of high reactivity.
The reactivity of a metal is indicated by its position in the activity series.
The methods employed for the extraction of metals of different reactivities
are listed here alongwith the activity series. An aluminium plant

The methods of metal extraction summarized
K (Potassium) Most reactive metal
Ba (Barium) Highly reactive metals, e.g. alkali and alkaline
earth metals and aluminium are obtained by
Ca (Calcium) electrolytic reduction method.
Na (Sodium)
Mg (Magnesium) Oxides of moderately active metals, e.g. iron,
Al (Aluminium) lead, zinc, and tin can be reduced by heating
Zn (Zinc) Chemical reactivity with carbon (called carbon reduction method).
Fe (Iron) and tendency to lose Oxides of certain transition metals, e.g.
manganese dioxide, iron oxide, chromium oxide,
Ni (Nickel) electrons of metals etc. can be reduced by heating with aluminium
Sn (Tin) decreases in this (called aluminium reduction method).
Pb (Lead) direction

H (Hydrogen) Metal oxides of less reactive metals, e.g. copper,
mercury, lead can be reduced by heat alone,
Cu (Copper) (called self-reduction method).
Hg (Mercury)
Ag (Silver)
Au (Gold)
Pt (Platinum) Least reactive metal Found in native state (or free metallic state).

How are the metals of very low reactivity extracted
Metals such as platinum, gold and silver show very low reactivity. These
metals occur free in nature. So, these metals are obtained by simple physical
separation method. The heavier metal particles are separated from the sand
by hydraulic washing method.
How are the metals of low reactivity extracted
The sulphide ores of less reactive metals like Hg, Cu, Pb, etc. on heating in
the air, give the metal and SO . Gold panning—The oldest
2
method of gold extraction