Chemistry 8 : Particle Theory

Matter is considered anything that takes up space and has mass. All objects, including gases, liquids and solids are considered matter.

The particle theory essentially states that matter is made out of tiny particles which are constantly moving. These particles are held together by very electrical forces (protons and electrons). Particles are distant from eachother compared to its own size and each particle of a unique substance carries innate qualities that are different from other particles of other substances. Temperature affects the speed at which the particles move at. The higher the temperature, the faster the speed of the particles. The particle theory can be used to explain rates of reaction, diffusion, thermal conductivity, substance density, rate of dissolving, sublimation, evaporation and condensation as well as electrical conductivity and viscosity.

We are concerned with three different states that particles are in.

Solids have a rigid structure which are identified as having very strong electrostatic forces thus packed together. The particles always vibrate however they cannot move one place to another by themselves as objects. Solids carry vibrational energy

Liquids have a weaker force of attraction amongst one another. They are not confined as solid state particles and can bump against one another within any container. Water and oil are just two types of substances amongst many which are considered to be liquids at room temperature. Liquids carry translational energy and vibrational energy. Translational energy meaning being capable of moving up, down, side-to-side, diagonally, inwards, outwards, etc.

The forces of attraction that hold gases are much weaker than those of liquids and even weaker than solids in comparison. The movement of these particles are deterministically random and the forces that hold them together are weak thus causing them to be spread out. Gas particles can rotate, translate and vibrate. If you can imagine a balloon, it is easy to understand how gas particles behave within a restricted confinement of solids.

Intrinsinic properties which gases, liquids and solids depend on can be colour, odor, density and/or melting points.

Extrisinic properties which gases, liquids and solids depend on can be mass and volume.

Solids can become liquids or gases depending on the substance's boiling and vaporization point. Liquids can solidify by having its thermal energy removed or evaporized due to added thermal energy. Likewise, gases can condense due to a thermal energy being removed or transferred into a more dense form into liquids or solids.