Download - Physical changes
Physical changes
Brainstorm states of matter:
States of Matter Phase ChangeName
Energy Movement During Phase Change
Energy IN or Out
(absorbed or released)
The measure of the average energy of motion of the particles in a substance is
TEMPERATURE
Changes in state are physical changes
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A change that alters the form or appearance of a material butdoes not convert the material
into new substances.
PHYSICAL CHANGE
Transformation of Water (H2O)
Graph showing changes in temperature over time:Key Questions:
1. How does the graph show the transformation of water?
2. Describe the transformations that took place.
3. Describe what was happening at the particle level.
4. Make improvements in your graph. Show the following:
a. Diagram of particles at different stages/phases.
b. Label processes such as melting, condensing, boiling, evaporating (Refer to your photos)
c. Graph of volume of water over time
Organize your photos to create a short video-journal of the transformation of Water.
Temperature (degrees C
elsius)
Time (minutes)
0
100
Time-Temperature Graph for Water
Phase Diagram of Water
Temperature (degrees C
elsius)
Time (minutes)
0
100
Time- Temperature Graph for Water
Why is the slope of the graph flat (no temperature change) at 0 degrees?
Why is the slope of the graph flat (no temperature change) at 100 degrees even though the stove is still on?
What is true for the ice-water mixture when the temperature began to rise?
Why did temperature increase at a constant rate?
When will the temperature of the water rise above 100 degrees Celsius?
Temperature –Time Graph for heating water
Why is the slope of the graph flat (no temperature change) at 0 degrees and 100 degrees even though the stove is still on?
What is true for the ice-water mixture when the temperature began to rise?
Why did temperature increase at a constant rate?
When will the temperature of the water rise above 100 degrees Celsius?
Temperature –Time Graph for heating water
Why is the slope of the graph flat (no temperature change) at 0 degrees and 100 degrees even though the stove is still on?
What is true for the ice-water mixture when the temperature began to rise?
Why did temperature increase at a constant rate?
When will the temperature of the water rise above 100 degrees Celsius?
energy from stove = energy required for phase change. No temperature change
No ice remains- only water for temp to increase
Constant stove temp, constant amount of water
When only water vapor remains- one state of matter
Temperature (degrees C
elsius)
Time (minutes)
0
100
Time- Temperature Graph for Water
As the temp approaches melting point temperature, the KE of the water molecules increases loosening the bonds between water molecules.
As the ice begins to melt, additional heat energy does not raise the temperature of the water, but loosens the bonds changing ice to water. i.e. phase change – melting.
Once the water is in a liquid phase, increasing the amount of heat input raises the temp of the liquid water.
As the temp approaches boiling point, the KE of the molecules is sufficient to allow the separation of molecules into the gas phase.
As the liquid begins to boil. Additional input of heat energy does not raise the temperature of the water, rather it is used to break water bonds. i.e. phase change.
Once the water is in the gas phase, additional heat input raises the temperature of the water vapor Note: greater energy is needed to vaporize water than to melt it. WHY?
Phase Change- Meltingenergy from stove = energy required for phase change
No temperature change
Phase Change- Vaporizationenergy from stove = energy required for phase change
No temperature change
Energy from stove causes increased KE and increased Temperature
Energy from stove causes increased KE and increased Temperature
Two states of Matter
Two states of Matter
One state of Matter
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http://www.media.pearson.com.au/schools/cw/au_sch_whalley_sf1_1/int/2_slg.htmlAnimation- particles and sublimation
Matter changes whenever energy is added or taken away.
Energy is added: Solid Liquid Gas
Energy is removed: Gas Liquid Solid
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