Properties of Matter

Properties of Solid:

Solids have a definite shape and volume.
They are characterised by strong intermolecular forces that keep their particles closely packed together.
Solids are incompressible, meaning that they cannot be easily compressed into a smaller volume.
They have a high density compared to liquids and gases.
Solids have a definite melting point, which is the temperature at which they transition from a solid to a liquid state.
They exhibit rigidity, meaning that they resist deformation and maintain their shape even under external pressure.
Solids can be classified as crystalline or amorphous based on the arrangement of their particles.
Crystalline solids have a regular and repeating pattern of particles, while amorphous solids have a disordered arrangement.
They can conduct heat and electricity, but the extent of their conductivity depends on the nature of the solid and its composition.
Solids can undergo physical changes such as melting, boiling, sublimation, and deposition, but their chemical properties remain unchanged.

Properties of Liquids:

Liquids have a fixed volume but no fixed shape.
They can flow and take the shape of their container.
Liquids are denser than gases but less dense than solids.
They have intermolecular forces that hold their molecules together.
They have a definite boiling and melting point.
Liquids can be compressed but only to a very small extent.
They have a definite surface tension, which allows them to form droplets.
Liquids can be miscible or immiscible depending on their polarity and intermolecular forces.
They can conduct electricity but only when they are ionised or contain ions.
Liquids can dissolve other substances and form solutions.

Properties of Gases:

Gas has no definite shape or volume
It can expand to fill any available space
Gas molecules are in constant motion and move randomly in all directions
Gas exerts pressure on its surroundings
The volume of gas is affected by changes in temperature and pressure
Gases can be compressed to occupy a smaller volume
The density of gases is lower than that of solids and liquids
Gases have low viscosity and flow easily
Gas can be liquefied or solidified by reducing temperature and/or increasing pressure.

Properties of Gases:

The kinetic molecular theory explains the behaviour of gases such as Diffusion, Effusion, Pressure, compressibility, Mobility and Density which are defined below;

Diffusion:

Diffusion is the process by which particles move from an area of high concentration to an area of low concentration. It is a fundamental process in science that occurs in many different contexts, such as in gases, liquids, and solids.

There are many examples of diffusion that occur in our everyday lives. Here are some common examples:

Perfume: When you spray perfume, the fragrance diffuses throughout the room.
Tea: When you stir sugar into your tea, the sugar particles diffuse from an area of high concentration (where you added the sugar) to an area of low concentration (the rest of the tea).
Food colouring: If you drop a drop of food colouring into a glass of water, the colour will gradually diffuse throughout the water.

Effusion:

Effusion is the process by which a gas or a substance in a gaseous state escapes through a small opening or a porous material. This can happen due to the difference in pressure between the two sides of the opening or material, causing the gas or substance to move from an area of high pressure to an area of low pressure. The rate of effusion depends on the size of the opening or material, the pressure difference, and the molecular weight of the gas or substance.

Example:

Smoke diffuses into the air.
Flower smell, garbage stink or body odour.

Pressure:

The force exerted by gaseous particles per unit area is called gas pressure. It can be expressed mathematically as.

Pressure =Force/Area

P = F/A = M/m2

The S.I unit of force is Newton (N) and unit of area is m², hence pressure has S.I unit of S.I unit of Nm^-2. It is also known as Pascal (Pa). 1 Pascal =1 Nm^-2. .

Compressibility:

Compressibility is a measure of how much the volume of a substance decreases when subjected to an applied pressure.

Mobility:

Mobility refers to the ability to move or be moved from one place to another. In the context of transportation, mobility often refers to the ease with which people or goods can travel between different locations. For example, a person who can walk or bike to school has more mobility than someone who must rely on a car or public transportation. In general, the term mobility can be used to describe the movement of people, goods, or information.

Density:

Density is a measure of how much mass is contained within a given volume. It is usually expressed in units of mass per unit volume, such as grams per cubic centimetre (g/cm³) or kilograms per cubic metre (kg/m³). The formula for density is:

Density = mass / volume