The World of Metals and Non-Metals - Visual Reference Guide

1

Physical Properties of Metals

Malleability: Can be beaten into thin sheets with a hammer.
Gold & Silver are the most malleable! Aluminium foil is used for packing food.
Ductility: Can be drawn into thin, long wires.
1 gram of Gold can be drawn into a 2 kilometer-long wire!
Sonority: Produces a clear, ringing sound when struck. (e.g., Temple bells, school bells, instruments like Sitars).
Heat Conduction: Metals are Good Conductors of Heat.
* Hot Water Experiment: Metal spoon gets hot instantly, wooden spoon remains cold.
Electrical Conduction: Metals are Good Conductors of Electricity.
* Tester Experiment: Copper wire and Aluminium foil make the bulb glow; Sulfur & Carbon do not.

CRITICAL EXCEPTIONS:

- Mercury (Hg): The only metal found as a liquid at room temperature.
- Sodium (Na) & Potassium (K): Super soft metals; can be easily cut with a kitchen knife!

2

Rusting & Corrosion

When Iron objects are left exposed to moist air, they develop a brown flaky deposit called Rust.

The Formula:
Iron (Fe) + Oxygen (O2) + Water (H2O) → Hydrated Iron Oxide (Rust)

Experiment (Activity 4.5):

Tube A
Silica Gel (Dry Air)
No Rust

Tube B
Boiled Water + Oil
No Rust

Tube C
Water + Air
RUSTS!

Rust Prevention: Painting, oiling, greasing, or applying a protective layer of Zinc metal (Galvanisation).

Copper Corrosion: Copper forms a dull green coating when exposed to moisture.

Silver Corrosion: Silver gets a black coat over time due to sulfur gases.

Ancient Indian Metallurgy:
The Iron Pillar of Delhi (Chandragupta II, ~1600 years old, 8m tall, 6000kg+) stands outdoors and has barely rusted!

3

Oxide Chemistry Battle

1. Metals form Basic Oxides

Magnesium Ribbon burns with a dazzling white flame to form Magnesium Oxide (MgO) white powder.

Mg + O2 --(Burn)→ MgO
MgO + H2O → Mg(OH)2 (Magnesium Hydroxide)

Litmus Test: Turns Red Litmus BLUE (Basic!).

2. Non-Metals form Acidic Oxides

Burning Sulfur Powder in a deflagrating spoon produces Sulfur Dioxide (SO2) gas.

S + O2 → SO2
SO2 + H2O → H2SO3 (Sulfurous Acid)

Litmus Test: Turns Blue Litmus RED (Acidic!).

Sodium (Na): Reacts violently with water/air. Stored in Kerosene.

Phosphorus (P): Catches fire easily in air. Stored safely in Water.

4

Non-Metals in Action!

Non-metals are not just "un-metals"—they are absolutely vital for life and technology!

OXYGEN (O2) Essential for respiration of all living organisms.

CARBON (C) The key component of proteins, fats, carbs, and all life forms.

NITROGEN (N) Used in chemical fertilizers to boost agricultural growth.

CHLORINE (Cl) Crucial for water purification (killing harmful microbes).

IODINE (I) Applied on wounds as an antiseptic solution (Tincture of Iodine).

What are Alloys? Homogeneous mixtures of metals (or metals + non-metals) engineered for higher strength and resistance to corrosion (e.g., Stainless steel, brass).

5

Quick Glossary & Concepts

Elements

Basic building blocks of matter that cannot be broken down chemically. There are currently 118 elements known to science.

Corrosion

The slow eating-away of metals due to interaction with environmental gases, moisture, and chemical pollutants.

Brittleness

The tendency of materials to shatter into small fragments upon impacts (e.g., Coal and Sulfur break instantly when hit with a hammer).

Did You Know?

Steel cables (which support heavy loads in giant suspension bridges and construction cranes) are made of a strong mixture of Iron (metal) and Carbon (non-metal)!

6

Comparison Matrix

Property	Metals	Non-metals
Appearance	Lustrous (Shiny)	Dull (Non-lustrous)
State	Hard Solids (Except Hg)	Solids, Liquids, Gases (Soft/Brittle)
Malleable?	Yes	No (Brittle)
Ductile?	Yes	No
Conductors	Excellent (Heat & Electricity)	Very Poor (Insulators)
Oxide Nature	Basic (Red litmus → Blue)	Acidic (Blue litmus → Red)

"Study systematically and master your exams!"