Special Properties of Matter:
Matter can be broadly categorized by its properties. These properties are what define the physical characteristics and behavior of a substance. Here are some special properties of matter, with definitions and examples:
1. Physical Properties: These properties can be observed or measured without changing the chemical composition of the substance.
a) Density: The ratio of mass to volume. A substance's density determines whether it will float or sink in a liquid.
* Example: Wood is less dense than water, so it floats. Lead is denser than water, so it sinks.
b) Viscosity: A fluid's resistance to flow. A liquid with high viscosity flows slowly, while a liquid with low viscosity flows quickly.
* Example: Honey is highly viscous, while water has low viscosity.
c) Conductivity: The ability of a material to conduct electricity or heat.
* Example: Metals are good conductors of electricity, while rubber is a good insulator.
d) Malleability: The ability of a material to be hammered or rolled into thin sheets without breaking.
* Example: Gold is highly malleable and can be beaten into very thin sheets.
e) Ductility: The ability of a material to be drawn into wires without breaking.
* Example: Copper is ductile and is used to make electrical wires.
f) Melting Point: The temperature at which a solid changes into a liquid.
* Example: The melting point of ice is 0°C (32°F).
g) Boiling Point: The temperature at which a liquid changes into a gas.
* Example: The boiling point of water is 100°C (212°F).
2. Chemical Properties: These properties describe how a substance reacts with other substances and how it changes its chemical composition.
a) Flammability: The ability of a substance to burn in the presence of oxygen.
* Example: Gasoline is highly flammable, while water is not.
b) Reactivity: The tendency of a substance to undergo chemical reactions.
* Example: Sodium is highly reactive with water, while gold is relatively unreactive.
c) Oxidation: The chemical reaction of a substance with oxygen.
* Example: Iron oxidizes (rusts) in the presence of oxygen and moisture.
d) Corrosion: The deterioration of a material due to chemical reactions.
* Example: Metals can corrode when exposed to certain chemicals, such as acids.
3. Other Special Properties:
a) Magnetism: The ability of a material to attract or repel other magnetic materials.
* Example: Iron is a ferromagnetic material and is strongly attracted to magnets.
b) Elasticity: The ability of a material to return to its original shape after being deformed.
* Example: A rubber band is elastic and can be stretched and then returns to its original length.
c) Hardness: The resistance of a material to scratching or indentation.
* Example: Diamond is the hardest naturally occurring substance.
d) Solubility: The ability of a substance to dissolve in a solvent.
* Example: Sugar is soluble in water, while oil is not.
These are just a few examples of the many special properties of matter. By understanding these properties, we can predict how substances will behave and use them effectively in different applications.