Matter is composed of tiny particles known as constituent particles, which can be atoms or molecules.

A constituent particle is the basic unit that makes up a substance, such as an atom or molecule.

Interparticle spaces are the spaces between the particles in a substance, where other particles can exist, like dissolved sugar in water.

Solids have a definite shape and volume due to closely packed particles with strong interparticle attractions.

Heating a solid increases the kinetic energy of particles, allowing them to overcome interparticle attractions and change to a liquid.

The melting point is the temperature at which a solid changes its state to a liquid.

Liquids take the shape of their container because their particles can move freely but are still close together.

Gas particles have high kinetic energy and move freely in all directions, leading to no fixed shape or volume.

The boiling point is the temperature at which a liquid converts to gas due to increased energy causing particles to escape.

Evaporation occurs at any temperature at the surface, while boiling occurs at a specific temperature throughout the liquid.

Applying pressure decreases the volume of air as particles are pushed closer together, demonstrating gas compressibility.

Liquids have a definite volume but no definite shape, adapting to the shape of their container.

Thermal energy refers to the energy that affects the movement of particles; higher thermal energy means faster particle movement.

Solids: tightly packed; Liquids: slightly spaced; Gases: widely spaced and free to move.

Heating increases thermal energy, causing particles to vibrate more and move apart in solids and liquids.

This is characteristic of solids, where particles are held closely and do not move freely.

Solids are not compressible due to their tightly packed particles that have little space to move closer together.

Sugar dissolves in water, while sand does not; sugar’s particles occupy spaces between water particles.