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Matter
Matter
All matter is made up of particles known as atoms. Atoms are the simplest possible particles, but they often are grouped together to form molecules.
All matter is made up of particles known as atoms. Atoms are the simplest possible particles, but they often are grouped together to form molecules.
Matter that is made up of only one type of atom is known as an Element. For example, Iron only contains Iron atoms and Oxygen only contains Oxygen atoms.
Matter that is made up of only one type of atom is known as an Element. For example, Iron only contains Iron atoms and Oxygen only contains Oxygen atoms.
Elements are the simplest of all substances. They cannot be chemically broken down into anything smaller. They are the building block from which the Universe is made.
Elements are the simplest of all substances. They cannot be chemically broken down into anything smaller. They are the building block from which the Universe is made.
There are 92 naturally occurring Elements and (as of October 2020) there are 26 artificial Elements which have been made in a lab.
There are 92 naturally occurring Elements and (as of October 2020) there are 26 artificial Elements which have been made in a lab.
The most common way to display all the known Elements is in a table called the Periodic Table.
The most common way to display all the known Elements is in a table called the Periodic Table.
Properties of a Material
Properties of a Material
The 'properties of a material' are its characteristics and how it behaves as a material. Properties can be split into 2 groups; Physical and Chemical.
The 'properties of a material' are its characteristics and how it behaves as a material. Properties can be split into 2 groups; Physical and Chemical.
Density
Density
Density is a measure of how much mass is inside a given volume of the material. Density is measured in kilograms per cubic metre (kg/m³). Below are some examples of materials and their densities :
Density is a measure of how much mass is inside a given volume of the material. Density is measured in kilograms per cubic metre (kg/m³). Below are some examples of materials and their densities :
Water
Water
Density : 1,000 kg/m³
Density : 1,000 kg/m³
Lead
Lead
Density : 11,340 kg/m³
Density : 11,340 kg/m³
Helium
Helium
Density : 0.17 kg/m³
Density : 0.17 kg/m³
Ice
Ice
Density : 920 kg/m³
Density : 920 kg/m³
Density : Floating & Sinking
Density : Floating & Sinking
Density detemines if a substance sinks or floats in a liquid.
Density detemines if a substance sinks or floats in a liquid.
If the density of a material is LESS than the density of the liquid, it FLOATS.
If the density of a material is LESS than the density of the liquid, it FLOATS.
If the density of a material is MORE than the density of the liquid, it SINKS.
If the density of a material is MORE than the density of the liquid, it SINKS.
An Iceberg floats because ice is less dense than the water around it.
An Iceberg floats because ice is less dense than the water around it.
A hot air ballon rises into the air because the hot air inside the balloon is less dense than the colder air around it.
A hot air ballon rises into the air because the hot air inside the balloon is less dense than the colder air around it.
Electrical Conductivity
Electrical Conductivity
Electrical conductivity is a measure of a material's ability to conduct electric current.
Electrical conductivity is a measure of a material's ability to conduct electric current.
If a material EASILY CONDUCTS electric currents, it is known as a CONDUCTOR.
If a material EASILY CONDUCTS electric currents, it is known as a CONDUCTOR.
If a material DOES NOT EASILY conduct electric currents, it is known as an INSULATOR.
If a material DOES NOT EASILY conduct electric currents, it is known as an INSULATOR.
In the diagram above, the bulb lights when the steel paper clip is used because steel is a conductor. When the plastic toy is used the bulb does not light because plastic is an insulator.
In the diagram above, the bulb lights when the steel paper clip is used because steel is a conductor. When the plastic toy is used the bulb does not light because plastic is an insulator.
The general rule is :
The general rule is :
Why are conductors conductors?
Why are conductors conductors?
Insulators
Insulators
In insulators, the electrons which carry electric charge are bound tightly to their atoms. This means they can't move through the material, so an electric current doesn't flow.
In insulators, the electrons which carry electric charge are bound tightly to their atoms. This means they can't move through the material, so an electric current doesn't flow.
Conductors
Conductors
In conductors, the electrons which carry electric charge are only loosely bound to their atoms. This means they move easily through the material, so an electric current can flow.
In conductors, the electrons which carry electric charge are only loosely bound to their atoms. This means they move easily through the material, so an electric current can flow.
Elasticity
Elasticity
Elasticity is a measure of the ability of a material to return to its original shape and size after being deformed (squashed or stretched).
Elasticity is a measure of the ability of a material to return to its original shape and size after being deformed (squashed or stretched).
If a material RETURNS to its original size or shape after being stretched, it is ELASTIC.
If a material RETURNS to its original size or shape after being stretched, it is ELASTIC.
If a material DOES NOT RETURN to its original size or shape after being stretched, it is INELASTIC.
If a material DOES NOT RETURN to its original size or shape after being stretched, it is INELASTIC.
Elastic Materials
Elastic Materials
Rubber is used in elastic bands as rubber is a very elastic material. When stretched to many times its original size, it can still return to normal when the stretching force is removed.
Rubber is used in elastic bands as rubber is a very elastic material. When stretched to many times its original size, it can still return to normal when the stretching force is removed.
Inelastic Materials
Inelastic Materials
Copper is used in wires as it is a good electrical conductor and can be drawn into long thin wires, without returning to its original size. This makes copper an inelastic material.
Copper is used in wires as it is a good electrical conductor and can be drawn into long thin wires, without returning to its original size. This makes copper an inelastic material.
Elasticity : Bouncing Balls
Elasticity : Bouncing Balls
Balls bounce when dropped because they are made of elastic materials. These materials allow the ball to deform upon impact and then spring back to its original shape, resulting in a high bounce.
Balls bounce when dropped because they are made of elastic materials. These materials allow the ball to deform upon impact and then spring back to its original shape, resulting in a high bounce.
Corrosion Resistance
Corrosion Resistance
Corrosion resistance is the ability of a material to withstand corrosion, which is the deterioration of a material due to chemical reactions with its environment. Types of corrosion include rusting, tarnishing or forming a patina.
Corrosion resistance is the ability of a material to withstand corrosion, which is the deterioration of a material due to chemical reactions with its environment. Types of corrosion include rusting, tarnishing or forming a patina.
Corrosion : Rusting
Corrosion : Rusting
Rusting occurs when iron reacts with oxygen and water to form the compound iron oxide, which is more commonly called Rust. Rust is a reddish-brown flaky substance that can weaken the metal over time, as the rust flakes away exposing fresh iron to the air.
Rusting occurs when iron reacts with oxygen and water to form the compound iron oxide, which is more commonly called Rust. Rust is a reddish-brown flaky substance that can weaken the metal over time, as the rust flakes away exposing fresh iron to the air.
Rusting of metal parts globally costs $2.5 trillion USD a year, soa variety of methods are used to prevent or reduce rusting.
Rusting of metal parts globally costs $2.5 trillion USD a year, soa variety of methods are used to prevent or reduce rusting.
This photo shows the progression from pure iron on the left, to rusted iron on the right.
This photo shows the progression from pure iron on the left, to rusted iron on the right.
A simple experiment that can show that both water and oxygen are needed for rusting to occur is shown below :
A simple experiment that can show that both water and oxygen are needed for rusting to occur is shown below :
The word equation for rusting is :
The word equation for rusting is :
The rusting of iron can be prevented through a range of methods :
The rusting of iron can be prevented through a range of methods :
Coating
Coating
Applying a layer of paint or plastic over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
Applying a layer of paint or plastic over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
Oiling
Oiling
Applying a layer of oil or grease over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
Applying a layer of oil or grease over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
Electroplating
Electroplating
Using electroysis to apply a thin layer of a corrosion resistant metal over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
Using electroysis to apply a thin layer of a corrosion resistant metal over the iron prevents water and oxygen coming into contact with the iron, preventing rusting.
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