Changes of State

Vaporization

As liquid water is heated, it temperature rises until it reaches 100 C. At this point, liquid water changes into water vapor. The change from a liquid to a gas is known as vaporization

Change of state

Matter can change from one state to another when thermal energy is absorbed or released. This change is known as change of state.

Sublimation

Some substances can change from the solid state to the gas state without ever becoming a liquid. During this process, known as sublimation, the surface particles of the solid gain enough energy to become a gas

Energy

The ability to do work or cause change

Temperature

The average kinetic energy of the individual particles is the temperature, an intensive property.

Freezing

The change from the liquid state to the solid state is called freezing. As the liquid cools, it loses thermal energy. As a result, its particles slow down and come closer together.

Melting

The change from the solid state to the liquid state is called melting. The temperature at which a substance changes from a solid to a liquid is called the melting point. The melting point of water is 0 C

Kinetic Energy

The energy of motion is called kinetic energy. Particles within matter are in constant motion. The amount of motion of these particles depends on the kinetic energy they possess.

Heat

The movement of thermal energy from a substance at a higher temperature to one at a lower temperature is called heat. When a substance is heated, it gains thermal energy. therefore, its particles move faster and its temperature rises. When a substance is cooled, it loses thermal energy, which cause its particles to move more slowly and its temperature to drop.

Freezing Point

The temperature at which a substance changes from the liquid state to the solid state is called the freezing point. The freezing point of the liquid state of a substance is the same temperature as the melting point of the solid state. Liquid water freezes at 0 C

Thermal Energy

The total kinetic and potential energy of all the particles in sample of matter is called thermal energy. Thermal energy, an extensive property, depends on the number of particles in a substance as well as the amount of energy each particle has.

Evaporation

Vaporization that takes place at the surface of a liquid is called evaporation. Evaporation, which occurs at temperatures below the boiling point.

Boiling

Vaporization that takes place below the surface of a liquid is called boiling. The temperature at which a liquid boils is called the boiling point. The boilng point of water is 100 C

Condensation

When particles move slowly enough for their attractions to bring them together, droplets of liquid form. This process, which is the opposite of vaporization, is called condensation. As a gas condenses to a liquid, it releases the thermal energy it absorbed to become a gas