The things or objects, which we all use in our daily life are made up of different types of materials Examples: Pen, Book, Chair etc....
Material is a substance that is used for making things. A material could be used to make a large number of different objects. An object could be either made of a single type of material or of many different types of materials.
All these materials have mass, shape, uses and are classified based on many criteria, including their physical states, properties of materials, etc.
GENERAL PROPERTIES OF MATERIAL
1. Appearance:
The "appearance" property of a material refers to how it looks or the visual characteristics it presents.
Here are some factors related to the appearance property of materials:
A) Size and Shape: The physical dimensions and form of the material. The size and shape of objects made from the material can influence its overall appearance.
B) Color: Different materials exhibit a wide range of colors, and color can significantly impact the visual appeal.
C) Texture: This is the feel or surface characteristics of a material. Texture can be smooth, rough, bumpy, glossy, matte, etc.
D) Luster: Material could be shiny ( luster or luster ) or could be rough (non- lustrous). All metals are lustrous (like Gold, Silver Aluminium etc...), some are more while the others is less whereas wood, rubber etc. are non-lustrous.
2. Hardness:
The material could be hard and soft. For example Rocks, iron etc. are hard.
Hard materials may be :
A) Brittle: Those materials which break into smaller pieces or are powdered when hammered. For example, rock, glass, salt.
B) Malleable: Materials that can be spread into thin sheets when beaten.
For example, metals are malleable.
C) Ductile: Materials that can be drawn into thin and long wires.
For example, metals are ductile as well. Materials like wood, rubber, and fiber are soft.
3. Transperancy:
Materials can be classified based on their transparency, which refers to the degree to which they allow light to pass through. The three primary categories are transparent, translucent, and opaque.
A) Transparent Materials:
Definition: Materials that allow almost all light to pass through, and objects can be clearly seen through them.
Examples: Glass, Clear plastics, Water (in thin layers), Air (to some extent)
B) Translucent Materials:
Definition: Materials that allow some light to pass through but scatter it in a way that objects on the other side are not clearly visible.
Examples: Frosted glass, Wax paper, Tinted car windows, Some types of plastics
C) Opaque Materials:
Definition: Materials that do not allow any light to pass through, blocking the view of objects on the other side.
Examples: Wood, Metal, Brick, Cardboar
4. Good and bad conductor of electricity
Materials can be classified based on their electrical and thermal conductivity. Conductivity is a measure of how well a material allows the flow of electricity or heat. Here are the main classifications based on conductivity:
A) Electrical Conductors:
Definition: Materials that allow the easy flow of electrical charge (electricity).
Examples: Metals (copper, aluminum, silver), Graphite, Some solutions (electrolytes)
B) Electrical Insulators:
Definition: Materials that do not allow the flow of electrical charge.
Examples: Rubber, Glass, Wood, Plastic etc...
C) Semiconductors:
Definition: Materials with intermediate conductivity, between conductors and insulators.
Examples: Silicon, Germanium etc…
5. Good and bad conductor of heat
Materials can be classified based on their electrical and thermal conductivity. Conductivity is a measure of how well a material allows the flow of electricity or heat. Here are the main classifications based on conductivity:
A) Thermal Conductors:
Definition: Materials that allow the easy flow of heat.
Characteristics:
Efficient at conducting heat.
Heat is transferred through the material quickly.
Examples: Metals (copper, aluminum), Diamond, Silver
B) Thermal Insulators:
Definition: Materials that will not allow the flow of heat.
Characteristics:
Poor conductors of heat.
Reduce heat transfer.
Examples: Wood, Styrofoam, Fiberglass, Rubber
6. Combustible And Non-Combustible substances:
Materials can be classified based on their behavior during combustion, which is the process of burning. Combustion involves a chemical reaction between a material and oxygen, typically resulting in the release of heat and the formation of new substances. Here are the main classifications based on combustion:
A) Combustible Materials:
Definition: Materials that can undergo combustion, burning when exposed to an ignition source and oxygen.
Characteristics:
Can support combustion.
Release heat and often produce flames during burning.
Examples: Wood, Paper, Oil, Gasoline
B) Non-Combustible Materials:
Definition: Materials that do not easily catch fire or burn under normal conditions.
Characteristics:
Do not support combustion
Generally fire-resistant.
Examples: Metals (e.g., iron, aluminum), Glass, Stone, Concrete
7. Ability to float/sink in water
Materials can be classified based on their ability to float or sink in a given fluid, usually water. Those materials that sink in water are denser than the water whereas the material which floats on water is less dense than water.
Here are the main categories:
A) Buoyant Materials:
Definition: Materials that float on the surface of a fluid.
Characteristics: Density is lower than the density of the fluid.
Examples: Wood (less dense than water), Cork, Styrofoam
B) Sinking Materials:
Definition: Materials that sink in the fluid.
Characteristics: Density is higher than the density of the fluid.
Examples: Metals (e.g., iron, leaD), Most rocks and minerals, Glass
8. Based on solubilities:
Materials can be classified based on their solubility, which refers to the ability of a substance (solvent) to dissolve in another substance (solvent) to form a homogeneous mixture. Here are the main classifications based on solubility:
A) Soluble Materials:
Definition: Materials that can dissolve in a particular solvent.
Characteristics:
Have molecules or ions that can be dispersed in the solvent.
Examples: Salt (sodium chloride) is soluble in water. Sugar (sucrose) is soluble in water.
B) Insoluble Materials:
Definition: Materials that do not dissolve in a particular solvent.
Characteristics: Have molecules or ions that do not interact significantly with the solvent.
Examples: Sand is generally insoluble in water.Certain metals, like copper, are insoluble in water.
9. Miscible and Immiscible Liquid:
Miscibility refers to the ability of two liquids to mix and form a homogeneous solution. Conversely, immiscibility refers to the inability of two liquids to form a homogeneous mixture. Here's a classification based on the miscibility or immiscibility of liquids:
A) Miscible Liquids:
Definition: Two liquids that can mix in any proportion to form a homogeneous solution.
Characteristics:
Complete mixing without phase separation.
No visible boundary between the two liquids.
Examples: Water and ethanol, Acetone and methanol, Gasoline and ethanol
B) Immiscible Liquids:
Definition: Two liquids that do not mix and form separate layers when combined.
Characteristics:
Limited or no mixing occurs.
Clearly visible boundary between the two liquids.
Examples: Oil and water, Hexane and water, Olive oil and vinegar
GROUPING OF MATERIALS
Materials are classified into groups together on the basis of similarities and differences
in their properties. This is done for convenience and to study their properties easily
Here are some group of objects that can be grouped
1. Objects made up of wood.
2. Objects made up of fibre.
3. Objects made up of metal.
4. Objects made up of ceramic.
5. Objects made up of glass.
6. Objects made up of plastic.
7. Objects made up of rubber.
8. Some things are liquids e.g. oil.
What are the advantages of classification?
The several advantages of the classification of material is given below:
A) It helps in the identification of objects.
B) It helps in the sorting of the objects.
C) It also helps in locating things when unable to find it.
D) It makes the study of different objects easy and meaningful instead of
studying each material separately from each other which becomes hard.
(e) It helps to understand similarities and dissimilarities between the objects
around us