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METALS AND NON METALS
Physical Properties of Metals
Metals are fascinating materials that surround us in
everyday life, from the aluminum in our soda cans to
the iron in our cars
...
Let’s dive into these properties step by
step, using examples and anecdotes to bring the topic
to life
...
Luster: The Shine of Metals
Metals are known for their shiny appearance, a
property called luster
...
For example, think of a polished silver
spoon or the gleaming surface of a gold ring
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This is
why gold can be beaten into gold leaf, which is so thin
it’s almost transparent
...
The metal didn’t crack or shatter—it
just kept spreading out, like dough under a rolling pin
...
Ductility: Stretching Metals
Metals can also be drawn into wires, a property known
as ductility
...
The video
showed a machine pulling a copper rod through a
series of dies, gradually thinning it into a wire
...


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This is due to the “sea of electrons” in their
atomic structure, which allows energy to flow freely
...
Similarly, a simple circuit with a copper
wire lit up a bulb instantly, demonstrating electrical
conductivity
...
Density: Heavy but Strong
Metals are generally dense, meaning they have a high
mass per unit volume
...
In the video, a comparison
was made between a wooden block and a metal block
of the same size
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For
instance, tungsten has a melting point of 3,422°C,
which is why it’s used In light bulb filaments
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This is why bells are made of
metals like bronze
...
This property is also
why metal utensils clink when they touch each other
...
Hardness: Resistance to Deformation
While metals are generally hard, their hardness varies
...
In the video, a
nail was driven into a wooden board effortlessly, while
a piece of sodium crumbled under pressure
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Steel
cables in suspension bridges are a perfect example
...
The
amount of force it endured was astonishing
...


Color: More Than Just Silver and Gold

While many metals are silver or gray, some have
unique colors
...
The video displayed a
collection of metal samples, each with its distinct
color, reminding us that metals are not just functional
but also beautiful
...
Whether it’s the luster
of gold, the conductivity of copper, or the strength of
steel, their physical properties make them essential to
our modern world
...
Let’s dive into their reactivity, behavior with
acids, and other key characteristics, step by step, with
examples and anecdotes to make the journey
engaging
...
Reactivity of Metals
Metals vary in their reactivity, which determines how
they interact with other substances
...
In one of the videos, a
small piece of sodium was dropped into water, and it
fizzed violently, producing hydrogen gas and heat
...
Copper, for example, reacts slowly
with oxygen to form a greenish layer of copper
carbonate (patina) over time, as seen in the Statue of
Liberty
...
Reaction with Acids
Metals react with acids to produce hydrogen gas and a
salt
...

Copper (Cu), on the other hand, does not react with
dilute acids because it is below hydrogen in the
reactivity series
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For example:

Magnesium (Mg) burns brightly in air to form
magnesium oxide (MgO):
2Mg + O₂ → 2MgO
The video showed a magnesium ribbon burning with a
dazzling white flame, leaving behind a white powder of
MgO
...
This was
illustrated with a time-lapse of an iron nail left outside,
gradually turning reddish-brown
...
Displacement Reactions
A more reactive metal can displace a less reactive
metal from its compound
...
Over time, the blue color faded, and a
reddish-brown layer of copper formed on the nail
...
Corrosion and Prevention
Corrosion is the gradual destruction of metals by
chemical reactions with their environment
...
The video showed how
painting or galvanizing (coating with zinc) can prevent
rusting
...
Alloys: Enhancing Metal Properties
Alloys are mixtures of metals designed to improve
properties like strength and resistance to corrosion
...
The video demonstrated how stainless
steel remains shiny even after exposure to moisture,
unlike ordinary steel
...
Practical Applications
Metals are everywhere! From aluminum foil in
kitchens to gold in jewelry, their chemical properties
make them versatile
...

Gold (Au) is unreactive and retains its luster, making it
perfect for coins and ornaments
...
Their reactivity,
behavior with acids, and ability to form alloys are just a
few reasons why metals are so integral to our world
...
Metals are not just lying around in their
pure form; they are often found as compounds within
ores
...

Let’s start with native metals, which are metals found
in their pure, uncombined state
...
These metals are rare
because they don’t easily react with other elements
...
They’ve been
washed down from mountains over millennia, and
their resistance to corrosion keeps them intact
...
Take
iron, for example
...
These ores are mined, and the iron

is extracted through a process called smelting, where
the ore is heated with carbon to reduce the metal
oxide to pure metal
...
It’s the most
abundant metal in the Earth’s crust, but it’s always
found combined with other elements, primarily in
bauxite ore (Al₂O₃·2H₂O)
...

Now, let’s talk about step-by-step calculations
...
First, you’d calculate the molar mass of hematite:
Fe₂O₃: (2 × 55
...
7 g/mol
If you have 100 grams of hematite, the mass of iron in
it would be:

(2 × 55
...
7 × 100 = 69
...

Metals are also found in seawater
...
The
reaction looks like this:
Mg²⁺ + CaO + H₂O → Mg(OH)₂ + Ca²⁺
The magnesium hydroxide is then converted to
magnesium chloride, which is electrolyzed to produce
pure magnesium
...
For example, sulfide ores like
chalcopyrite (CuFeS₂) are often found near ancient
volcanic sites
...

One of the most captivating examples of metal
occurrence is gold veins in quartz
...
Miners often follow these veins deep into the
Earth, a process that has been romanticized in
countless stories and films
...
While not
naturally occurring, alloys like bronze (copper and tin)
and steel (iron and carbon) have shaped human
civilization
...

Metals are everywhere, from the depths of the Earth to
the devices we use daily
...


Properties of Ionic Compounds

Ionic compounds are fascinating materials with
unique properties that arise from their structure and
bonding
...

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These forces
are incredibly strong, which means it takes a lot of
energy to break them apart
...
Imagine
trying to melt a block of salt on your stove—it’s not
happening! This high thermal stability is why ionic
compounds are often used in high-temperature
applications, like in the production of ceramics
...
Solubility in Water

Many ionic compounds are soluble in water, but not
all
...

For instance, NaCl dissolves easily in water because
the water molecules surround the Na⁺ and Cl⁻ ions,
pulling them apart
...
Think of it like trying to dissolve a rock in
your tea—it just won’t work!
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...
However, when dissolved in water
or melted, they become excellent conductors
...
This is why ionic solutions are used
in batteries and electrolysis processes
...
Brittleness
Ionic compounds are brittle and tend to shatter when
struck
...
Imagine stacking two magnets with the
same poles facing each other—they push apart! This is
exactly what happens in ionic crystals like magnesium
oxide (MgO), which is used in refractory materials
because of its hardness and brittleness
...
Crystal Lattice Structure
Ionic compounds form crystal lattices, highly ordered
3D structures where each ion is surrounded by ions of
the opposite charge
...
This arrangement maximizes the attractive
forces and minimizes repulsion, creating a stable
structure
...


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Its ionic nature allows it to dissolve in
water, enhancing the flavor of food
...

Aluminum Oxide (Al₂O₃): Used in abrasives and
ceramics because of its hardness and high melting
point
...
From the salt on your dinner
table to the materials in your smartphone, ionic
compounds are everywhere!
Refining of Metals: A Journey from Ore to Pure Metal
The process of refining metals is a fascinating journey
that transforms raw, impure ores into pure, usable
metals
...

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These impurities can include other metals,
non-metals, or even gases trapped within the ore
...

For example, copper refining starts with copper ore,
which contains impurities like iron, sulfur, and silica
...
99% pure
...
Methods of Refining

There are several methods of refining metals, each
tailored to the specific properties of the metal and the
nature of its impurities
...
Electrolytic Refining
This method is widely used for refining metals like
copper, silver, and gold
...
The pure metal deposits on the cathode, while
the impurities settle as anode mud
...
The impure copper
anode is placed in an electrolytic cell filled with a
copper sulfate solution
...
The impurities, including gold
and silver, collect at the bottom as sludge
...
Zone Refining

This technique is used for ultra-pure metals required
in semiconductors and electronics
...
Impurities concentrate in the
molten zone and are carried to the end of the rod
...
A
rod of silicon is slowly passed through a heating coil,
creating a molten zone
...

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The impure metal is heated
to its boiling point, and the vapor is condensed to
obtain the pure metal
...
The zinc vapor rises and is
condensed in a separate chamber, leaving behind
impurities like lead and iron
...
Real-World Applications
Refining is not just a laboratory process; it has realworld implications
...
The high purity ensures minimal resistance,
making the wires efficient conductors of electricity
...
The removal of impurities
enhances the metal’s luster and conductivity
...
Challenges in Refining
While refining is a powerful process, it comes with its
own set of challenges:
Energy Consumption: Refining processes, especially
electrolytic refining, require significant amounts of
energy
...


Waste Management: The by-products of refining, such
as anode mud and slag, need to be managed carefully
to prevent environmental pollution
...
The Human Touch
Behind every refined metal is a story of human
ingenuity and perseverance
...
Her passion for the field
is evident as she describes the satisfaction of seeing a
dull, impure ore transform into a gleaming, pure metal
...
A Glimpse into the Future
As technology advances, so do refining techniques
...
The video
concludes with a glimpse of a futuristic refinery, where
automation and AI are used to monitor and optimize
refining in real-time
...
It’s a process that not only transforms
raw materials but also shapes the world we live in, one
pure metal at a time
...
It’s a natural
process, but one that can be controlled and prevented
using various methods
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This can be done through:

Painting or Coating: Applying a layer of paint, plastic,
or another non-reactive material to the metal surface
...

Galvanizing: Coating iron or steel with a layer of zinc
...
A hand-drawn plot in the video
showed how the zinc layer gradually degrades over
time, but the steel remains intact
...
Cathodic Protection
This method involves making the metal a cathode in
an electrochemical cell, which prevents it from
corroding
...

The reactive metal corrodes instead
...


Impressed Current: Using an external power source to
force electrons onto the metal, making it a cathode
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For example:
Stainless Steel: Made by adding chromium to steel
...
In the video, we saw how stainless
steel cutlery remains shiny and rust-free even after
years of use
...
Environmental Control
Changing the environment around the metal can also
prevent corrosion
...
In the video, we saw how

museums use dehumidifiers to protect ancient metal
artifacts
...
For example, in car radiators, inhibitors are
added to the coolant to prevent rust
...
Design Considerations
Sometimes, the best way to prevent corrosion is
through smart design
...
In the video, we saw how
redesigning a metal joint to eliminate crevices
extended its lifespan
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Regular inspections
and maintenance are crucial
...
In the video, we saw
how regular cleaning of a car’s undercarriage can
prevent rust
...

By combining these methods, we can effectively
prevent corrosion and extend the life of metal
structures and objects
...




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