Unit 6- Matter


Change-Cambiar, Cambio







Boiling-Hirviendo, Ebullición





Reverse Sublimation-Sublimación Inversa


Melting Point- Temperatura de Fusión

Boiling Point- Temperatura de Ebullición

Hang Out (clothes)- Colgar

Heat- Calentar

Rise- Subir



Changes of State

A change in temperature can cause a change of state in matter.  These are the changes of state:

Melting.  This is when a solid becomes a liquid, like when ice melts and changes to water.

Solidification.  This is when a liquid becomes a solid. It happens at the same temperature as melting.

Vaporization.  This is when a liquid becomes a gas.  It can happen in two ways:

Boiling.  Vaporization happens quickly when the substance reaches             a certain temperature.  When we heat water, it starts to boil and turns to water vapor.

Evaporation.  Vaporization happens slowly and at a lower temperature than boiling.  For example, water evaporates when we hang clothes out to dry.

Condensation.  This happens when a gas becomes a liquid.  Water vapor from the shower forms drops of water on a mirror.

Sublimation.  This is when a solid becomes a gas without first becoming a liquid.  For example, solid air fresheners change into a gas when they mix with the air.

Reverse Sublimation.  This is when a gas becomes a solid without first becoming a liquid.  For example, water vapor in the air turns into frost.

Every pure substance changes from a solid to a liquid at a specific temperature, this is called the melting point.  The boiling point is another specific property of a substance.

Over the years people have learned how to make use of the changes of state.  Melting and solidification are used to manufacture many objects.  Some metals and plastics are heated until they are liquids.  Then they are put into molds and left to become solid.