A state of matter is one of the distinct forms that matter can take on. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. Each state has distinct physical properties and behavior.

1. Solid

- Characteristics: Solids have a fixed shape and volume. The particles in a solid are tightly packed and held together by strong intermolecular forces. They have a definite shape and can only change shape if an external force is applied.

- Examples: Ice, rock, wood, metal

2. Liquid

- Characteristics: Liquids have a definite volume but no fixed shape. The particles in a liquid are close together but not as tightly packed as in a solid. They can move past each other and take the shape of the container they are in.

- Examples: Water, oil, milk, gasoline

3. Gas

- Characteristics: Gases have neither a fixed shape nor a fixed volume. The particles in a gas are far apart and have high kinetic energy. They move freely and spread out to fill the entire container.

- Examples: Air, helium, hydrogen, nitrogen

4. Plasma

- Characteristics: Plasma is a hot, ionized gas. It is the fourth state of matter and occurs at very high temperatures, such as in the sun and stars. The electrons in a plasma are separated from the atoms, creating a soup of charged particles.

- Examples: Lightning, solar flares, aurora borealis