Chemistry

Metallurgy Process

All Mock Test

SSC CGL

NABARD

Insurance

RBI Assistant

SSC CHSL

IBPS PO

SBI PO

CAPF

Metallurgy Process

The process of extracting metal in pure form from its ore is known as metallurgy.

Minerals

The compound of a metal found in nature is called a mineral. A mineral may be a single compound or a complex mixture.

Ores

Those minerals from which metal can be economically and easily extracted are called ores.
All ores are minerals, but not all minerals are ores.

Gangue (or Matrix)

The ore is generally associated with earthy impurities like sand, rocks, and limestone known as gangue or matrix.

Flux

A substance added to ore to remove impurities is called flux.

There are two types of flux:

Acidic Flux: Added to remove basic impurities.
- Example: SiO₂ + FeO → FeSiO₃ (acidic flux + basic impurity → ferrous silicate)
Basic Flux: Added to remove acidic impurities.
- Example: CaCO₃ + SiO₂ → CaSiO₃ + CO₂ (basic flux + acidic impurity → calcium silicate)

Slag

The combination of gangue with flux in ores forms a fusible material called slag.

Example 1: Gangue + CaO → Slag

Example 2: SiO₂ + CaO → CaSiO₃

Concentration of Ore

The process of removing gangue from the ore is known as concentration of ore. It can be carried out in the following ways depending on the nature of the ore:

Gravity Separation
Magnetic Concentration
Froth Flotation Process
Chemical Methods

Relative Reactivity of Metals

The reactivity of metals in decreasing order is:

K (Potassium) → Na (Sodium) → Ca (Calcium) → Mg (Magnesium) → Al (Aluminium) → Zn (Zinc) → Fe (Iron) → H (Hydrogen) → Hg (Mercury) → Cu (Copper) → Ag (Silver) → Au (Gold)

Calcination

Calcination is a process in which ore is heated, generally in the absence of air, to expel water from hydrated oxide or carbon dioxide from a carbonate, at temperatures below their melting points.

Example 1: Al₂O₃ · 2H₂O → Al₂O₃ + 2H₂O
Example 2: CaCO₃ → CaO + CO₂

Roasting

Roasting is a process in which ore is heated, usually in the presence of air, at temperatures below its melting point.

Example 1: ZnS + 2O₂ → ZnSO₄
Example 2: CuS + 2O₂ → CuSO₄

Smelting

The reduction of oxide ore with carbon at high temperature is known as smelting.

Example 1: Fe₂O₃ + 3C → 2Fe + 3CO
Example 2: PbO + C → Pb + CO

Activity Series of Metals

A series is obtained by arranging metals in decreasing order of reactivity, known as the activity series.

Important Metals and Their Ores

Metal	Ores
Sodium (Na)	Chile saltpeter (NaNO₃), Trona (Na₂CO₃, 2NaHCO₃ · 3H₂O), Borax (Na₂B₄O₇ · 10H₂O), Common salt (NaCl)
Aluminium (Al)	Bauxite (Al₂O₃ · 2H₂O), Corundum (Al₂O₃), feldspar(KAlSi₃O₈),, Cryolite (Na₃AlF₆), Alunite (K₂SO₄ · Al₂(SO₄)₃ · 4Al(OH)₃), Kaolin (3Al₂O₃ · 6SiO₂ · 2H₂O)
Potassium (K)	Nitre (saltpetre) (KNO₃), Carnalite (KCl · MgCl₂ · 6H₂O)
Magnesium (Mg)	Magnesite (MgCO₃), Dolomite (MgCO₃ · CaCO₃), Epsom salt (MgSO₄ · 7H₂O), Kieserite (MgSO₄ · H₂O)
Calcium (Ca)	Dolomite (CaCO₃ · MgCO₃), Calcite (CaCO₃), Gypsum (CaSO₄ · 2H₂O), Fluorspar (CaF₂), Asbestos (CaSiO₃ · MgSiO₃)
Strontium (Sr)	Strontianite (SrCO₃), Celestite (SrSO₄)
Copper (Cu)	Cuprite (Cu₂O), Copper glance (Cu₂S), Copper pyrites (CuFeS₂)
Silver (Ag)	Ruby Silver (3Ag₂S · Sb₂S₃), Horn Silver (AgCl)
Gold (Au)	Calaverite (AuTe₂), Silvenites ([(Ag, Au)Te₂])
Barium (Ba)	Barytes (BaSO₄)
Zinc (Zn)	Zinc blende (ZnS), Zincite (ZnO), Calamine (ZnCO₃)
Mercury (Hg)	Cinnabar (HgS)
Tin (Sn)	Cassiterite (SnO₂)
Lead (Pb)	Galena (PbS)
Antimony (Sb)	Stibnite (Sb₂S₃)
Cadmium (Cd)	Greenockite (CdS)
Bismuth (Bi)	Bismuthinite (Bi₂S₃)
Iron (Fe)	Hematite (Fe₂O₃), Limonite (2Fe₂O₃ · 3H₂O), Magnetite (Fe₃O₄), Siderite (FeCO₃), Iron Pyrite (FeS₂)
Cobalt (Co)	Smelite (CoAsS₂)
Nickel (Ni)	Millerite (NiS)
Manganese (Mn)	Pyrolusite (MnO₂), Magnetite (Mn₂O₃ · 2H₂O)
Uranium (U)	Carnotite (K(UO)₂ · VO₄ · 3H₂O), pitchblende (U₃O₈)

Alloys

An alloy is a metallic, intimately mixed solid mixture of two or more different elements, at least one of which is metal.

Alloys are homogeneous in the molten state but may be homogeneous or heterogeneous in the solid state.

Important Alloys and Their Uses

Brass: Cu (70%) + Zn (30%) – Used in making utensils.
Bronze: Cu (90%) + Sn (10%) – Used in making coins, bells, and utensils.
German Silver: Cu (60%) + Zn (20%) + Ni (20%) – Used in making utensils.
Rolled Gold: Cu (90%) + Al (10%) – Used in making cheap ornaments.
Gun Metal: Cu (88%) + Sn (10%) + Zn (1%) + Pb (1%) – Used in making guns, barrels, gears, and bearings.
Delta Metal: Cu (60%) + Zn (38%) + Fe (2%) – Used in making blades of aeroplanes.
Munz Metal: Cu (60%) + Zn (40%) – Used in making coins.
Dutch Metal: Cu (80%) + Zn (20%) – Used in making artificial ornaments.
Monel Metal: Cu (70%) + Ni (30%) – Used for base-containing containers.
Rose Metal: Bi (50%) + Pb (28%) + Sn (22%) – Used in making automatic fuses.
Solder: Pb (50%) + Sn (50%) – Used for soldering.
Magnalium: Al (95%) + Mg (5%) – Used for the frame of aeroplanes.
Duralumin: Al (94%) + Cu (3%) + Mg (2%) + Mn (1%) – Used in making utensils.
Type metal: Sn (5%) + Pb (80%) + Sb (15%) – In printing industry
Bell metal: Cu (80%) + Sn (20%) – For casting bells, statues
Stainless Steel: Fe (75%) + Cr (15%) + Ni (10%) + C (05%) – For making of utensils and surgical cutlery
Nickel Steel: Fe (95%) + Ni (05%) – For making electrical wire and automobile parts.

Amalgam

An amalgam is an alloy in which one of the component metals is mercury.
In alloys, the chemical properties of the component elements are retained, but certain physical properties are improved.

Compounds of metal and non-metal and their uses:

Ferrous oxide (FeO): In green glass, ferrous salt.
Ferric oxide (Fe₃O₄): In electroplating of ornaments and formation of ferric salt.
Ferrous sulphate (FeSO₄·7H₂O): In the dye industry and Mordh’s salt.
Ferrous hydroxide [Fe(OH)₃]: In laboratory reagents and in making medicines.
Iodine (I₂): (i) (i) (i) (i) (i)an antiseptic,tic, (in) In making tincture of iodine.
Brom(Br₂): (i)r₂): (i)the dye dye industry, (as a) As laboratory reagent.
Chlorine (Cl₂): In the form of (i) (i) (i) mustard gas and (ii) bleaching powder.
Hydrochloric acid (HCl): In the formation of aqua regia (3HCl : 1HNO₃) and dyes.
Sulphuric a(H₂SO₄): (i)O₄): (i) As a reagent, (in)the purificationtion of petroleum, (iii) In lead storage battery.
Sulphur dioxide (SO₂): (i)O₂: (i) As oxidants & reductants, a bleaching/leaching agent.
Hydrogen Sulphides (H₂S): In qualitative analysis of basic radical (group separation).
Sulphur (S): Antiseptivulcanisationtion of rubbgunpowder,der, medicine.
Ammonia (NH₃):a reagentgentan ice ice factorPhosphorous: (i)ous: (i) Red (P₄) refrigerant,the matchatch indu, etc., andtc., (ii) White (P₄rat-killingling medicine.
Producer gas (CN₂): (i)N₂): (i) In heating furnace, (ii) Cheap fuel, (iii) In extraction of metal.
Water gas (CO + H₂): (i) As fuel, (ii) Welding work.
Coal gas: (i) As fuel, (ii) Inert atmosphere.
Nitrous oxide (N₂laughinghing gsurgery.ery.
Carbon dioxide (COSoda water,tfireFire extinguisher.
Carbon monoxide (CO): In phosgene gas (COCl₂).
Graphite: As electrodes.
Diamond: Ornamenglasslass cuttirockRock drilling.
A[K₂SO₄Al₂(SO₄)₃·24H₂O]: (i)₂O]: (i) Purification of water, (ii) Leather industry.
Aluminium sulphate [Al₂(SO₄)₃·18H₂O]:the paperaper industry/fextinguishers.her.
Anhydrous aluminium chloride (AlCl₃): Cracking of petroleum.
Mercuric Chloride (HgCl₂): Calomel, Insecticides (CorrosSublimate).te).
Mercury oxide (HgO): Ointment, poison.
Mercury (Hg): Thermometer vermillion, amalgam.
Zinc Sulphide (ZnS): White pigment.
Zinc Sulphate (ZnSO₄·7H₂O): Lithopoeye Eye ointment.
Zinc Chloride (ZnCl₂): Textile industry.
Zinc oxide (ZnO): Ointment.
Zinc (Zn): In battery.
Calcium carbide (CaC₂): Calcium cyanide & acetylene gas.
Bleaching powder [Ca(OCl)Cl]: Insecticidbleachinghing actions.
PlasterParisaris [(CaSO₄)₂·2H₂O / CaSO₄·½H₂O]: Statue, Surgery.
Calcium sulphate (CaSO₄·2H₂O): Cement industry.
Calcium carbonate (CaCO₃): Lime & toothpaste.
Copper sulphate (CuSO₄·5H₂insecticides,delectrictric cells.
Cupric oxide (CuO): Blue & green glass, purification of petroleum.
Cuprous Oxide (Cu₂O): Red glass, pesticides.
Copper (Cu): Electrical wire.
Sodium nitrate (NaNOfertiliser.zer.
Sodium Sulphate (Na₂SO₄·10H₂O): Medicine, cheap glass.
Sodium bicarbonate (NaHCO₃): Fire extinguisher, bakery, reagent.
Sodium Carbonate (WashSoda): (i)da): (i) Glass industry, (ii) Paper industry, (iii) Removal of permanent hardness of water, (iv) Washing.
Hydrogen peroxide (H₂Ooxidantsants & reductaninsecticides.des.
Heavy water (D₂O): Nuclear reactor.
Liquid hydrogen: Rocket fuel.
PlasterParisaris [(CaSO₄)₂·2H₂O / CaSO₄·½H₂O]: Statue, Surgery. Plaster of Paris is obtained by heating gypsum at 120°Quicklime:ime: Calcium oxide (CaO).
Slaked lime: Ca(OH)₂.

Final Thoughts

Metallurgy is the scientific process of extracting pure metals from their ores. It begins with identifying minerals and ores, where ores are minerals from which metals can be economically extracted. During extraction, gangue (impurities) is removed using flux, forming slag. Methods like calcination, roasting, and smelting help purify the metal further.

The activity series of metals determines their reactivity and extraction method. Metals like iron, copper, zinc, and aluminium are derived from key ores suchhaematite,ite, chalcopyrite, and bauxite.

Various alloys like brass, bronze, and steel enhance metal strength and utility, while metal compounds such as CuSO₄, CaCO₃, and ZnO serve important industrial and medicinal purposes.