Phase Change Diagrams

Phase Change Diagrams

​Quick Recap...

​During yesterday's lab, your data should have made a graph that looked something like this... ---->

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​This is a phase change diagram

​Phase Change Diagrams

• ​Write this on your Notes Paper

• ​Graphical representation of matter changing states

• ​Compares the temperature (y axis) and the time (x axis)

• ​As temperature increase - energy increases

  • ​Molecules can "break free" and change to a new state of matter​

• ​Shows specific temperatures (melting, boiling, etc.) and the states of matter!

​Sample Diagram

Multiple Choice

Is the graph pictured Endothermic or Exothermic?

• Endothermic

• Exothermic

​Phase Change Diagram

​​Write this on your Notes Paper

• Endothermic!

• ​The temperature is increasing, so energy is being absorbed

Multiple Choice

What state of matter would this substance be between points A & B?

• Solid

• Liquid

• Gas

​Phase Change Diagram

​Solid!

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​The substance is at it's coldest temperature here, resulting in Solid Matter

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​**Draw/highlight on your graph what you see on the right**

Multiple Choice

What state of matter would this substance be between points C & D?

• Solid

• Liquid

• Gas

​Phase Change Diagram

Liquid!

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The temperature has increased past it's melting point.

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​**Draw/highlight on your graph what you see on the right**

Multiple Choice

What state of matter would this substance be between points E & beyond?

• Solid

• Liquid

• Gas

​Phase Change Diagram

Gas!

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The temperature is at its highest, which means it has a lot of energy.

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​**Draw/highlight on your graph what you see on the right**

​Phase Change Diagram

Write this on your notes paper:

• ​The flat plateaus - specific temperatures (melting and boiling points)

  • ​In an exothermic graph - freezing and condensation points

• ​​Where molecules start to "change" into the next state of matter

• ​**Draw/highlight on your graph what you see on the right**