phase changes looking at boiling, melting, and freezing points, evaporation and condensation
TRANSCRIPT
Phase Changes
Looking at Boiling, Melting, and Freezing points, Evaporation and
Condensation
Physical science series: phases of matter 18 min video
• http://player.discoveryeducation.com/index.cfm?guidAssetId=CCAD037E-5E2D-4AC3-9929-090E6277C929&blnFromSearch=1&productcode=US
Phase Change
• Matter can change from one phase to another.
• This is called a Phase Change
Phase Changes
• The amount of heat energy in any particular piece of matter can change.
• A big enough change in heat energy causes a phase change.
• Solids Liquids Gas
• There are different names for each of the phase changes.
Add Heat Energy Add Energy
Different names for each Phase Change
vocabulary• Melting- change
from a solid to a liquid
• Vaporization – change from liquid to gas.– Boiling– Evaporation
• Condensation- change from a gas to a liquid.
• Freezing – change from a liquid to a solid.
• Sublimation – change from a solid to a gas
Vaporization
• Difference between boiling and evaporation– Evaporation – happens at
the surface – usually due to sun’s energy.
– Boiling happens within the liquid. Inside of liquid changes to a gas, this is why there are bubbles.
Phase Changes
• Decrease temp- – Condensation– Freezing
• Increase temp-– Melting– Sublimation– Evaporation– Boiling
Phase Changes are Caused by either an increase or decrease in heat energy (temperature).
Phase Change Points
• Each substance has a temperature that it changes phase at.– Different for all substances!– For example, freezing point for water is
0ºC. The freezing point for gold is approximately 1064ºC.
• boiling point, freezing point, melting point, condensation point all do not change if you have more or less of the substance.
• Temperatures at which one state turns to another……
• BOILING POINT- liquid turns to gas• MELTING POINT – solid turns to liquid• FREEZING POINT – liquid turns to solid
• BOILING POINT of water- 100 ˚ C (or above)• MELTING POINT of water - 0˚ C (or above)• FREEZING POINT of water- 0˚C (or below
Water
Interactive matter phase change
• http://www.miamisci.org/af/sln/phases/watersolid.html