Ch 07: Metals, Non-metals & Metallurgy

⚙️ Chapter At a Glance

Ag (Silver)

Best Conductor

Au (Gold)

Most Ductile Metal

Al (8%)

Most Abundant Metal in Crust

Liquid Metal

Liquid Non-metal

📘 Metal vs Non-metal

Metals: Electropositive → lose electrons → form cations
Non-metals: Electronegative → accept electrons → form anions
Exception for both: Hydrogen (behaves as both)

⚡ Reactivity Series (Most → Least Reactive)

›

🔴 More Reactive (extracted by electrolysis) → 🟡 Medium → 🟢 Less Reactive (found free in nature)

🔩 Properties of Metals

Hard, Shiny, Malleable and Ductile
Most ductile: Gold (Au), then Silver (Ag)
Good conductor of electricity and heat
Highest conductor: Ag (Silver) | Lowest conductor: Pb (Lead)
Surface shiny (Exception: Mercury, Caesium, Gallium — non-shiny)
Metal oxides = Alkaline (basic) in nature
Amphoteric oxides (react with both acid & base): Al, Zn, Pb

⭐ Important Metal Facts

Category	Metal
Strategic Metal	Titanium (Ti)
Liquid Metal	Mercury (Hg)
Radioactive Liquid Metal	Francium (Fr)
Most Abundant in Earth's Crust	Aluminium (Al) — 8%
Heaviest Metal	Osmium (Os)
Lightest Metal & Strongest Reducing Agent	Lithium (Li)
Most Ductile	Gold (Au)
Best Conductor	Silver (Ag)
Liquid Non-metal	Bromine (Br)

Diseases from Excess Metal

Excess Copper (Cu) → Wilson's Disease
Excess Mercury (Hg) → Minamata Disease

No Reaction with O₂ or Water

Ag, Au, Pb, Pt, Hg — do NOT react with oxygen and water

🔥 Flame Colours of Metals

Golden Yellow

Purple / Lilac

Red Violet

Crimson Red

Apple Green

Red (Fireworks)

⚠️ Exam Trap — Flame Colours

Na (Sodium) = Golden Yellow flame (street lamp colour)
K (Potassium) = Purple/Lilac
Ba (Barium) = Apple Green (fireworks)
Sr (Strontium) = Red in fireworks | Li = Crimson Red

Metal	Key Uses
Na (Sodium)	Street lamps (yellow light)
Cu (Copper)	Wires, utensils, foil
Al (Aluminium)	Wire, space industry
Hg (Mercury)	Thermometer, tube lights
Mg (Magnesium)	Flash bulb making
Fe (Iron)	Steel industry
Cd (Cadmium)	Moderator in nuclear reactors
Ba (Barium)	Green colour in fireworks
Sr (Strontium)	Red colour in fireworks

⚡ Reactivity Series — Full Detail

›

Activity Level	Metals	Extraction Method
Highly Active	K, Na, Ca, Mg, Al	Electrolysis (molten state)
Medium Active (Carbonate ore)	Zn, Fe, Pb, Cu	Calcination → Metal oxide → Reduction (Smelting)
Medium Active (Sulphide ore)	Zn, Fe, Pb, Cu	Roasting → Metal oxide → Reduction
Less Active	Ag, Au	Simple heating (found free/native in nature)

⚠️ Exam Trap — Reactivity

More reactive metal displaces less reactive metal from solution
Fe + CuSO₄ → FeSO₄ + Cu (Fe more reactive than Cu)
K, Na, Ca, Mg, Al extracted by electrolysis
Ag, Au found in native/free state in nature
H is placed between Pb and Cu in reactivity series

🪨 Important Ores of Metals

Metal	Important Ore	Formula
Aluminium (Al)	Bauxite (main ore)	Al₂O₃·2H₂O
Aluminium (Al)	Cryolite / Corundum	Na₃AlF₆ / Al₂O₃
Copper (Cu)	Chalcopyrite (main ore)	CuFeS₂
Iron (Fe)	Haematite (main ore)	Fe₂O₃
	Magnetite	Fe₃O₄
Lead (Pb)	Galena (main ore)	PbS
Zinc (Zn)	Zincblende / Calamine	ZnS / ZnCO₃
Manganese (Mn)	Pyrolusite (main)	MnO₂
Silver (Ag)	Argentite	Ag₂S
Calcium (Ca)	Calcite	CaCO₃
Magnesium (Mg)	Magnesite / Dolomite	MgCO₃ / CaMg(CO₃)₂
Cadmium (Cd)	Greenockite	CdS

⚠️ Exam Trap — Ores

Aluminium main ore = Bauxite (Al₂O₃·2H₂O)
Copper main ore = Chalcopyrite (CuFeS₂) (also contains Fe)
Iron main ore = Haematite (Fe₂O₃); Magnetite = Fe₃O₄
Lead ore = Galena (PbS)
Pyrolusite (MnO₂) = main ore of Manganese (used in dry cells)
Mineral vs Ore: All ores are minerals but not all minerals are ores

🌿 Non-Metals

Accept electrons → form anions (electronegative)
Total non-metallic elements: 22 (11 Gas, 1 Liquid, 10 Solid)
Bad conductor of electricity (Exception: Graphite = good conductor)
Hardest non-metal: Diamond
Liquid non-metal: Bromine (Br)
Non-metal oxides = Acidic in nature
Low melting and boiling points (mostly)
Not malleable, not shiny (mostly)

⚠️ Exam Trap — Non-metals

Graphite = non-metal but good conductor of electricity
Diamond = non-metal but hardest substance and very high MP
Bromine (Br) = only liquid non-metal at room temperature
Hydrogen = exception (can behave as both metal and non-metal)

Metalloids (Semi-metals)

Have BOTH metallic and non-metallic properties

Present only in p-block
Total metalloids: 8
Amphoteric oxides (react with both acid & base)
Boron fibre = bulletproof jackets, lightweight dense material for aircraft
Examples: B, Si, Ge, As, Sb, Te, Po, At

💨 Inert Gases (Noble Gases) — Group 18

Chemically inert (outer shell: 8 electrons — complete)
Total: 6 gases — He, Ne, Ar, Kr, Xe, Rn

Gas	Key Uses
Helium (He)	Balloons, light aircraft (non-flammable); artificial respiration (divers); nuclear reactor coolant
Argon (Ar)	Welding; incandescent electric bulbs; tube lights (Hg vapour + Ar)
Neon (Ne)	Neon signs (advertising)
Xenon (Xe)	Photography flash tubes; "Stranger gas"

🔧 Alloys

📘 Definition

Homogeneous mixture of two or more metals (or one metal + one non-metal) prepared in molten state.

Brass

Cu 70% + Zn 30%

Utensils, wires, pipes, parts

Bronze

Cu 80% + Sn 20%

Utensils, statues (oldest alloy)

German Silver

Cu 50% + Zn 30% + Ni 20%

Jewellery, utensils, statues

Solder

Sn 50% + Pb 50%

Metal plating, joining metals

Stainless Steel

Fe 70% + Cr 18% + Ni 8% + C 1%

Blades, valves, surgical instruments

Amalgam

Any metal + Mercury (Hg)

Dental fillings; Fe & Pt do NOT form amalgam

⚠️ Exam Trap — Alloys

Brass = Cu + Zn (NOT Cu + Sn) | Bronze = Cu + Sn
German Silver has NO silver — Cu + Zn + Ni
Stainless Steel: Cr (Chromium) gives rust resistance
Amalgam: Fe and Pt do NOT form amalgam with Mercury
Solder = Sn + Pb (low melting point alloy — melts easily)

💧 Hydrogen & Water

Hydrogen (H₂)

Discoverer: Henry Cavendish (1766)

Atomic mass: 1.008 | Symbol: H
Electronic config: 1s¹
One proton, one electron; NO neutron
Diatomic molecule (H₂)
70% of Universe by mass
0.15% of Earth's atmosphere
3rd most abundant on Earth
Uses: Rocket fuel, NH₃ synthesis, fuel cell

Water (H₂O)

Universal Solvent

pH = 7 (neutral, pure)
Max density, min volume at 4°C
Bond angle H–O–H = 104.5°
Density: Ice=0.917 | Water=0.997 | Gas=0.6
Colourless, tasteless, odourless

💧 Hard Water vs Soft Water

Hard Water

Contains dissolved Ca and Mg salts (sulphate, carbonate, chloride). No foam/lather with soap.

Temporary hardness: due to bicarbonates of Ca, Mg. Removed by Boiling or Clark's Method
Permanent hardness: due to sulphates & chlorides. Removed by Washing Soda, Calgon, Ion-exchange, Resin method

Soft Water

Free from Ca and Mg salts. Forms good lather/foam with soap. Rainwater is naturally soft water.

🧪 Heavy Water (D₂O) & H₂O₂

Heavy Water (D₂O)

Discovered by Harold Urey (1932). Oxide of Deuterium. Higher density than normal water.

Moderator in nuclear reactors
Studying mechanism of chemical reactions
Making deuterium compounds (CD₄, D₂SO₄)

Hydrogen Peroxide (H₂O₂)

Discovered by Thénard (1818). Also called Oxygenated Water. Acts as both oxidant and reducing agent.

Milk and wine testing
Hair bleaching & antiseptic
Rocket fuel
Making hydroquinone & tartaric acid

⚠️ Exam Trap — Water

Water max density at 4°C (NOT 0°C)
H–O–H bond angle = 104.5°
Temporary hardness removed by Boiling; Permanent by Washing Soda
Heavy Water = D₂O; discoverer = Harold Urey (1932)
Heavy water = nuclear reactor moderator
H₂O₂ discovered by Thénard (1818); is both oxidant and reducer

🏭 Metallurgy — Extraction Process

📘 Metallurgy

Process of extraction of metal from its ore. Ore → Concentration → Metal Oxide → Reduction → Metal → Refining.

Ore

→

Concentration of Ore

→

Metal Oxide

→

Reduction (Smelting)

→

Crude Metal

→

Refining

📋 Key Metallurgy Terms

Term	Definition	Key Details
Mineral	Naturally occurring inorganic solid with definite chemical composition & crystalline structure	Not all minerals are ores
Ore	Mineral from which metal can be extracted easily and economically	All ores are minerals
Flux	Converts infusible impurities into fusible slag	e.g., CaO (basic flux) or SiO₂ (acid flux)
Slag	Fusible waste formed by Flux + acidic/basic impurities	SiO₂, Al₂O₃ in slag
Calcination	Heating concentrated ore below melting point in absence/limited air	Removes volatile impurities; for carbonate ores
Roasting	Heating concentrated ore in excess air (reverberatory furnace)	For sulphide ores; oxidises impurities
Distillation	Purification method for low boiling metals	Zn, Cd, Hg
Liquation	Purification of low melting point metals	Sn, Hg, Pb

⚠️ Exam Trap — Metallurgy

Calcination = absence of air (carbonate ores); Roasting = excess of air (sulphide ores)
K, Na, Ca, Mg, Al extracted by Electrolysis (very reactive)
Ag, Au found free in nature (least reactive → simple heating)
Mineral ≠ Ore: Ore must be economically extractable
Flux converts gangue into slag (fusible, removable)
Distillation for Zn, Cd, Hg (low boiling) | Liquation for Sn, Hg, Pb (low melting)

🎯 High-Frequency BPSC/BSSC Exam Points

Best conductor = Silver (Ag); Lowest = Lead (Pb)
Most ductile = Gold (Au); Most abundant metal = Al (8% crust)
Liquid metal = Mercury (Hg); Lightest metal = Li
Heaviest metal = Osmium (Os); Strategic = Titanium (Ti)
Radioactive liquid metal = Francium (Fr)
Amphoteric metals: Al, Zn, Pb
Wilson's Disease = excess Copper; Minamata = excess Mercury
Reactivity series: K>Na>Ca>Mg>Al>Fe>Pb>H>Cu>Hg>Ag>Au
Na flame = Golden Yellow; K = Purple; Ba = Apple Green; Li/Sr = Red
No reaction with O₂/H₂O: Ag, Au, Pb, Pt, Hg
Bauxite (Al₂O₃·2H₂O) = main ore of Al | Haematite (Fe₂O₃) = main ore of Fe
Chalcopyrite (CuFeS₂) = main ore of Cu | Galena (PbS) = main ore of Pb
Graphite = non-metal but good conductor; Diamond = hardest non-metal
Bromine = only liquid non-metal
Brass = Cu+Zn | Bronze = Cu+Sn | German Silver = Cu+Zn+Ni (NO Ag)
Stainless Steel: Cr gives rust resistance
Amalgam: Fe and Pt do NOT form amalgam
Inert gases (6): He, Ne, Ar, Kr, Xe, Rn — Group 18
He = balloons, nuclear coolant; Ar = welding, bulbs; Xe = photography flash
Hydrogen: Cavendish (1766); 70% of universe; 0.15% of Earth's atmosphere
Water max density at 4°C; bond angle = 104.5°
Temp hardness removed by boiling; Permanent by Washing Soda
Heavy water D₂O: Harold Urey (1932); nuclear reactor moderator
H₂O₂: Thénard (1818); both oxidant and reducer
Calcination = no air; Roasting = excess air; Both → metal oxide

📋 Alloy Quick Reference

Alloy	Composition	Use
Brass	Cu 70% + Zn 30%	Utensils, wires
Bronze	Cu 80% + Sn 20%	Statues
German Silver	Cu+Zn+Ni	Jewellery
Solder	Sn 50% + Pb 50%	Plating
Stainless Steel	Fe+Cr+Ni+C	Surgical

⚠️ Most Common Exam Traps

Brass = Cu+Zn (NOT Cu+Sn)
German Silver has NO silver
Graphite = non-metal but conducts electricity
Water densest at 4°C (NOT 0°C)
H₂O₂ = both oxidant AND reducer
Fe & Pt do NOT form amalgam
Temporary hardness removed by Boiling; permanent by Washing Soda
Calcination = absent/limited air; Roasting = excess air
Most abundant metal in universe = H; in Earth's crust = Al
Minamata = Mercury | Wilson's = Copper

⚙️ Metals, Non-metals & Metallurgy