βš—οΈ Metals and Non-metals

Class X Chemistry β€’ Chapter 2 β€’ Enhanced Interactive Study Guide

By S.K.Sinha β€’ Free Test Maker.com

🌟 Introduction to Elements

Elements are the building blocks of matter. Based on their properties, elements are classified into metals, non-metals, and metalloids. Understanding these classifications helps us predict their behavior and applications.

Classification of Elements

βš™οΈ

Metals

~80% of elements

πŸ’¨

Non-metals

~17% of elements

πŸ”¬

Metalloids

~3% of elements

πŸ”¨ Physical Properties of Metals

Metals: Elements that tend to lose electrons and form positive ions (cations). They have characteristic physical and chemical properties that distinguish them from non-metals.

πŸ”§ Malleability

Definition: Ability to be hammered into thin sheets

Example: Aluminum foil, gold leaf

Reason: Metallic bonding allows layers to slide

🧡 Ductility

Definition: Ability to be drawn into thin wires

Example: Copper wires, silver threads

Application: Electrical cables, jewelry

✨ Metallic Luster

Definition: Shiny appearance when polished

Reason: Free electrons reflect light

Examples: Gold, silver, copper

⚑ Electrical Conductivity

Definition: Ability to conduct electricity

Best Conductors: Silver > Copper > Gold

Reason: Mobile electrons carry current

🌑️ Thermal Conductivity

Definition: Ability to conduct heat

Examples: Copper pots, aluminum cookware

Exception: Lead is a poor thermal conductor

πŸ”Š Sonority

Definition: Produce sound when struck

Examples: Bells, musical instruments

Application: Church bells, cymbals

πŸ”¬ Exceptional Cases

  • Mercury: Liquid metal at room temperature
  • Sodium & Potassium: Soft metals, can be cut with knife
  • Lead: Poor conductor of heat
  • Gallium: Melts in hand (melting point 29.8Β°C)
Property Typical Metals Exceptions
State at room temperature Solid Mercury (liquid)
Hardness Hard Sodium, Potassium (soft)
Melting Point High Gallium, Cesium (low)
Density High Lithium, Sodium (low)

πŸ’¨ Physical Properties of Non-metals

Non-metals: Elements that tend to gain electrons and form negative ions (anions). They have properties opposite to metals in many cases.

πŸ’Ž Brittleness

Definition: Break easily when hammered

Example: Sulfur, carbon (graphite)

Reason: Covalent bonds are directional

🌫️ Dull Appearance

Definition: No metallic luster

Exception: Iodine, graphite (shiny)

Reason: No free electrons to reflect light

🚫 Poor Conductors

Electrical: Insulators (except graphite)

Thermal: Poor heat conductors

Reason: No mobile electrons

πŸ“Š Variable States

Solid: Carbon, sulfur, phosphorus

Liquid: Bromine

Gas: Oxygen, nitrogen, chlorine

πŸ”¬ Special Non-metals

  • Graphite: Only non-metal that conducts electricity
  • Diamond: Hardest natural substance
  • Iodine: Non-metal with metallic luster
  • Bromine: Only liquid non-metal at room temperature

πŸ§ͺ Common Non-metals and Their Uses

Non-metal Symbol State Uses
Carbon C Solid Pencils, steel making, diamonds
Oxygen O Gas Respiration, combustion, medical
Sulfur S Solid Vulcanizing rubber, medicines
Chlorine Cl Gas Water purification, bleaching
Nitrogen N Gas Fertilizers, preserving food

βš›οΈ Chemical Properties

πŸ”¬ Electronic Configuration & Chemical Behavior

The chemical properties of elements depend on their electronic configuration, particularly the number of valence electrons (outermost electrons).

Na
β†’
Na⁺
+ e⁻
Valence Electrons: Electrons in the outermost shell that determine chemical properties.
Metals: 1-3 valence electrons (tend to lose)
Non-metals: 4-8 valence electrons (tend to gain)

⚑ Reaction with Oxygen

Metals with Oxygen:
4Na + Oβ‚‚ β†’ 2Naβ‚‚O (Basic oxide)
Sodium burns with golden flame
Non-metals with Oxygen:
C + Oβ‚‚ β†’ COβ‚‚ (Acidic oxide)
S + Oβ‚‚ β†’ SOβ‚‚ (Acidic oxide)
Form acidic oxides

πŸ’§ Reaction with Water

Reactive Metals:
2Na + 2Hβ‚‚O β†’ 2NaOH + H₂↑
Sodium floats and produces hydrogen gas
Less Reactive Metals:
Mg + Hβ‚‚O β†’ MgO + H₂↑ (with steam)
Magnesium reacts only with steam

Water Reactivity Order:

  • K, Na, Ca react vigorously with cold water
  • Mg reacts with hot water/steam
  • Al, Zn, Fe react with steam
  • Cu, Ag, Au do not react with water

πŸ§ͺ Reaction with Acids

Metal + Acid β†’ Salt + Hydrogen
Zn + 2HCl β†’ ZnClβ‚‚ + H₂↑
Hydrogen gas evolved (pop test)

Important Points:

  • Only metals above hydrogen in reactivity series react
  • Copper, silver, gold do not react with dilute acids
  • Nitric acid is an oxidizing agent (special case)
  • Hydrogen gas test: burns with 'pop' sound

πŸ“Š Reactivity Series

Reactivity Series: Arrangement of metals in order of their decreasing reactivity with water, acids, and oxygen.
Potassium (K)
Most Reactive
Sodium (Na)
React with cold water
Calcium (Ca)
Violent reactions
Magnesium (Mg)
React with steam
Aluminum (Al)
Protected by oxide layer
Zinc (Zn)
React with dilute acids
Iron (Fe)
Moderate reactivity
Lead (Pb)
Low reactivity
Hydrogen (H)
Reference point
Copper (Cu)
No reaction with dilute acids
Silver (Ag)
Noble metals
Gold (Au)
Least Reactive

πŸ”¬ Applications of Reactivity Series

  • Displacement Reactions: More reactive metal displaces less reactive
  • Extraction Methods: Determines extraction process
  • Corrosion Protection: Galvanization uses zinc
  • Storage: Reactive metals stored under oil

⚑ Displacement Reactions

Metal + Salt Solution β†’ New Metal + New Salt
Zn + CuSOβ‚„ β†’ ZnSOβ‚„ + Cu
Zinc displaces copper (blue β†’ colorless)
Cu + ZnSOβ‚„ β†’ No Reaction
Copper cannot displace zinc

🏭 Occurrence of Metals

Minerals: Naturally occurring compounds of metals in the earth's crust.
Ores: Minerals from which metals can be extracted profitably.
Metal Important Ores Chemical Formula Type
Aluminum Bauxite Alβ‚‚O₃·2Hβ‚‚O Oxide ore
Iron Hematite, Magnetite Feβ‚‚O₃, Fe₃Oβ‚„ Oxide ore
Copper Copper pyrites CuFeSβ‚‚ Sulfide ore
Zinc Zinc blende ZnS Sulfide ore
Lead Galena PbS Sulfide ore
Silver Argentite Agβ‚‚S Sulfide ore
Gold Native gold Au Free state

Occurrence Facts:

  • Most reactive metals occur as compounds (oxides, sulfides, carbonates)
  • Least reactive metals (Au, Ag, Pt) occur in free state
  • Aluminum is the most abundant metal in earth's crust (8%)
  • Iron is the second most abundant metal (4%)

βš—οΈ Extraction of Metals

Metallurgy: The science and technology of extracting metals from ores and refining them for use.

πŸ—οΈ Concentration

Removal of unwanted materials (gangue) from ore

Methods: Gravity separation, magnetic separation, froth flotation

πŸ”₯ Calcination/Roasting

Calcination: Heating carbonate/hydroxide ores in absence of air

Roasting: Heating sulfide ores in presence of air

⚑ Reduction

Removal of oxygen from metal oxides

Methods: Carbon reduction, electrolysis, displacement

✨ Refining

Purification of crude metal

Methods: Electrolytic refining, distillation

πŸ”¬ Extraction Methods Based on Reactivity

πŸ”‹ Highly Reactive Metals (K, Na, Ca, Mg, Al)

Method: Electrolysis of molten compounds

2Alβ‚‚O₃ β†’ 4Al + 3Oβ‚‚
Electrolysis at 950Β°C
  • Cannot be reduced by carbon (very reactive)
  • Requires high temperature and electricity
  • Most expensive extraction method

πŸ”₯ Moderately Reactive Metals (Zn, Fe, Pb, Cu)

Method: Reduction with carbon or carbon monoxide

ZnO + C β†’ Zn + CO
Feβ‚‚O₃ + 3CO β†’ 2Fe + 3COβ‚‚
In blast furnace
  • Carbon acts as reducing agent
  • Cost-effective method
  • Used in large-scale production

πŸ’Ž Least Reactive Metals (Ag, Au, Pt)

Method: Simple heating or found in free state

2Agβ‚‚S + 2Oβ‚‚ β†’ 4Ag + 2SOβ‚‚
Simple roasting
  • Occur in native state
  • Easy extraction
  • Used since ancient times

πŸ”₯ Thermite Reaction

Thermite Reaction: Highly exothermic displacement reaction used for welding railway tracks and crankshafts.
Feβ‚‚O₃ + 2Al β†’ Alβ‚‚O₃ + 2Fe + Heat
Temperature reaches ~2500Β°C

πŸ”₯ Thermite Process

🧱

Iron oxide
(Feβ‚‚O₃)

+
⚑

Aluminum
(Al)

β†’
πŸ”₯

Molten Iron
+ Heat

Applications:

  • Welding railway tracks
  • Repairing machine parts
  • Joining iron pieces
  • Emergency welding

πŸ›‘οΈ Corrosion and Prevention

Corrosion: Gradual destruction of metals by chemical reaction with environment (air, water, acids).
Fe

Fresh Iron

(Shiny silver)

β†’
Feβ‚‚O₃

Rusted Iron

(Reddish brown)

Rusting of Iron:
4Fe + 3Oβ‚‚ + 6Hβ‚‚O β†’ 2Feβ‚‚O₃·3Hβ‚‚O
Hydrated iron(III) oxide (rust)

πŸ›‘οΈ Methods of Preventing Corrosion

🎨 Painting

Principle: Barrier coating

Use: Iron gates, bridges

Effect: Prevents contact with air/water

πŸ›’οΈ Oiling/Greasing

Principle: Water-repelling layer

Use: Machine parts

Effect: Prevents water contact

⚑ Galvanization

Principle: Zinc coating

Use: Iron sheets, pipes

Effect: Zinc corrodes preferentially

πŸ”§ Chrome Plating

Principle: Chromium coating

Use: Car parts, taps

Effect: Corrosion-resistant layer

πŸ—οΈ Anodizing

Principle: Thick oxide layer

Use: Aluminum products

Effect: Enhanced protection

πŸ”¬ Alloying

Principle: Mix with other metals

Example: Stainless steel

Effect: Inherent resistance

πŸ” Special Cases

  • Aluminum: Forms protective Alβ‚‚O₃ layer (self-protection)
  • Copper: Forms green patina (CuCO₃) - protective layer
  • Silver: Tarnishes due to Hβ‚‚S in air (Agβ‚‚S formation)
  • Gold: Does not corrode (most noble metal)

πŸ”— Alloys

Alloy: Homogeneous mixture of two or more metals, or a metal with a non-metal, to improve properties.

🎯 Why Make Alloys?

  • Increase Strength: Steel is stronger than pure iron
  • Increase Hardness: Bronze is harder than copper
  • Prevent Corrosion: Stainless steel resists rusting
  • Lower Melting Point: Solder melts easily
  • Improve Appearance: Brass looks like gold

πŸ—οΈ Steel

Composition: Iron + Carbon (0.1-1.5%)

Properties: Strong, hard, malleable

Uses: Construction, tools, vehicles

πŸ›‘οΈ Stainless Steel

Composition: Iron + Chromium + Nickel

Properties: Corrosion resistant

Uses: Cutlery, medical instruments

🎺 Brass

Composition: Copper + Zinc

Properties: Golden color, malleable

Uses: Musical instruments, decorative

πŸ”” Bronze

Composition: Copper + Tin

Properties: Hard, strong, corrosion resistant

Uses: Statues, coins, bells

πŸ”§ Duralumin

Composition: Aluminum + Copper + Magnesium

Properties: Light, strong

Uses: Aircraft parts

πŸ”Œ Solder

Composition: Lead + Tin

Properties: Low melting point

Uses: Joining electrical wires

πŸ’ 18 Carat Gold

Composition: Gold (75%) + Silver/Copper

Properties: Hard, attractive

Uses: Jewelry

🦷 Amalgam

Composition: Mercury + Other metals

Properties: Sets at room temperature

Uses: Dental fillings

βš›οΈ Ionic Compounds

Ionic Compounds: Compounds formed by transfer of electrons from metals to non-metals, resulting in electrostatic attraction between oppositely charged ions.
Na⁺
⟷
Cl⁻
= NaCl

πŸ”¬ Properties of Ionic Compounds

πŸ”³ Physical State

At room temperature: Crystalline solids

Reason: Strong electrostatic forces

Structure: Regular geometric arrangement

🌑️ Melting & Boiling Points

Nature: High melting and boiling points

Reason: Strong ionic bonds

Example: NaCl melts at 801Β°C

πŸ’§ Solubility

In water: Generally soluble

In organic solvents: Generally insoluble

Reason: Water molecules surround ions

⚑ Electrical Conductivity

Solid state: Do not conduct

Molten/Aqueous: Good conductors

Reason: Mobile ions carry current

πŸ§ͺ Formation of Ionic Compounds

Sodium Chloride Formation:
Na β†’ Na⁺ + e⁻ (oxidation)
Cl + e⁻ β†’ Cl⁻ (reduction)
Na⁺ + Cl⁻ β†’ NaCl (ionic bond)
Magnesium Oxide Formation:
Mg β†’ Mg²⁺ + 2e⁻
O + 2e⁻ β†’ O²⁻
Mg²⁺ + O²⁻ β†’ MgO

Important Rules:

  • Metals lose electrons to form cations (+ve ions)
  • Non-metals gain electrons to form anions (-ve ions)
  • Total positive charge = Total negative charge
  • Ions achieve noble gas configuration
  • Formula represents simplest ratio of ions

πŸ§ͺ Interactive Quiz Section

1. Which metal is the best conductor of electricity?
A) Silver
B) Copper
C) Gold
D) Aluminum
2. Which non-metal conducts electricity?
A) Diamond
B) Graphite
C) Sulfur
D) Phosphorus
3. The process used to prevent rusting by coating with zinc is called:
A) Anodizing
B) Galvanization
C) Electroplating
D) Painting
4. Which alloy is used in aircraft manufacturing?
A) Brass
B) Bronze
C) Duralumin
D) Steel

πŸ“š Summary & Key Takeaways

🎯 Chapter Summary:

  • Metals are malleable, ductile, lustrous, and good conductors
  • Non-metals are brittle, dull, and poor conductors (except graphite)
  • Reactivity series helps predict metal behavior
  • Extraction method depends on metal's reactivity
  • Corrosion is prevented by barrier methods and alloying
  • Alloys have improved properties compared to pure metals
  • Ionic compounds form by electron transfer between metals and non-metals

πŸ”¬ Important Reactions to Remember

Metal + Acid β†’ Salt + Hydrogen
Metal + Water β†’ Metal hydroxide + Hydrogen
Metal + Oxygen β†’ Metal oxide
Thermite: Feβ‚‚O₃ + 2Al β†’ Alβ‚‚O₃ + 2Fe

πŸŽ“ Study Tips

πŸš€ Practice Problems

πŸ§ͺ Problem Set 1: Properties

  1. Why do metals conduct electricity while non-metals don't?
  2. Explain why aluminum doesn't corrode easily despite being reactive.
  3. What would happen if zinc is added to copper sulfate solution?
  4. Why is sodium stored under oil?

βš—οΈ Problem Set 2: Reactions & Equations

  1. Complete: Mg + HCl β†’ _____ + _____
  2. Write the reaction for extraction of iron from Feβ‚‚O₃
  3. What happens when calcium reacts with water?
  4. Balance: Al + CuSOβ‚„ β†’ Alβ‚‚(SOβ‚„)₃ + Cu

πŸ”¬ Problem Set 3: Applications

  1. Why is stainless steel preferred for surgical instruments?
  2. How does galvanization protect iron from rusting?
  3. Why are electrical wires made of copper and not silver?
  4. What is the advantage of using alloys over pure metals?

πŸ”¬ Advanced Concepts

🏭 Industrial Applications

⚑ Electrolytic Refining

Used to purify crude metals like copper

At Anode: Cu β†’ Cu²⁺ + 2e⁻
At Cathode: Cu²⁺ + 2e⁻ β†’ Cu
Pure copper deposits at cathode
  • Impurities settle as anode mud
  • 99.9% pure copper obtained
  • Used for electrical applications

πŸ—οΈ Blast Furnace (Iron Extraction)

Zone 1: Top (200Β°C)

Feβ‚‚O₃ + 3CO β†’ 2Fe + 3COβ‚‚

Zone 2: Middle (700Β°C)

C + Oβ‚‚ β†’ COβ‚‚
COβ‚‚ + C β†’ 2CO

Zone 3: Bottom (1500Β°C)

CaCO₃ β†’ CaO + COβ‚‚
CaO + SiOβ‚‚ β†’ CaSiO₃ (slag)

🌍 Environmental Impact

♻️ Recycling of Metals

🌱 Benefits

  • Saves energy (up to 95% for aluminum)
  • Reduces mining damage
  • Decreases landfill waste
  • Lower carbon emissions

πŸ“Š Recycling Facts

  • Aluminum: 100% recyclable
  • Steel: Most recycled material
  • Copper: Retains properties
  • Lead: 99% from recycling

🏭 Environmental Concerns

  • Mining destroys ecosystems and landscapes
  • Ore processing releases harmful gases (SOβ‚‚, COβ‚‚)
  • Acid mine drainage pollutes water bodies
  • Smelting consumes large amounts of energy
  • Metal extraction contributes to global warming

🎯 Exam Tips & Tricks

πŸ“ Memory Techniques

  • Reactivity Series: "Please Send Charlie's Monkeys And Zebras In Lead Cages Securely Guarded" (K, Na, Ca, Mg, Al, Zn, Fe, Pb, H, Cu, Ag, Au)
  • Extraction Methods: High reactivity = Electrolysis, Medium = Carbon, Low = Heat
  • Alloy Compositions: Steel = Iron + Carbon, Brass = Copper + Zinc
  • Corrosion Prevention: Paint, Oil, Galvanize, Chrome, Anodize, Alloy

⚠️ Common Mistakes to Avoid

❌ Don't Confuse

  • Malleability vs Ductility
  • Calcination vs Roasting
  • Corrosion vs Rusting
  • Alloy vs Amalgam

βœ… Remember

  • Graphite conducts electricity
  • Mercury is liquid metal
  • Gold occurs in free state
  • Aluminum forms protective oxide

πŸŽ‰ Congratulations!

You have completed Chapter 2: Metals and Non-metals! πŸŽ“

"The properties of metals and non-metals help us understand the material world around us!" 🌟

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πŸ“š freetestmaker.com | Anonymous | 2025-10-31 21:58:17