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
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