STATES OF MATTER AND PHASE CHANGES

 

 

 

Unit Introduction

In this unit, you will explore the states of matter and the conditions needed for Phase changes in matter.

 

 

Image result for states of matter

 

 

The States of Matter

Watch the following video clip as an introduction to the states of matter:

https://www.brainpop.com/science/matterandchemistry/statesofmatter/

Then, take the review quiz:

https://www.brainpop.com/science/matterandchemistry/statesofmatter/quiz/

 

There are three main states of matter that are possible for all substances. These states are solid, liquid, and gas. Each state of matter has its own unique characteristics.

 

State:

Solid

Liquid

Gas

Particle Arrangement:

packed tightly in regular formation

not as close, particles flow amongst each other

particles are far apart and fly around in all directions

Particle Movement/Energy:

slow vibration but particles mainly stay in place

faster movement, more energy than solids

fastest movement and highest energy among particles

Shape:

definite shape (holds its own shape)

no definite shape (takes shape of its container)

no definite shape

Volume:

definite volume

definite volume

no definite volume

Image:

Image result for states of matter solid

Image result for states of matter liquid

Image result for states of matter gas

 

 

Here is another diagram to help you further visualize the similarities and differences among the states of matter:

 

https://virtuallearningacademy.net/VLA/LessonDisplay/Lesson6075/SCIPSU10_Physical_States_Matter.png

 

Plasma is a less common state of matter that is found at extremely high temperatures produced by stars.

There is additional information regarding the states of matter and an introduction to phase changes in the following video clip. Pay close attention to the segment that starts around 8:45. The narrator will draw a phase change diagram and explain what conditions are needed for phase changes in matter.

 

 

 

STUDENT VIDEO GUIDED NOTES

 

Attach your completed guided notes document to question #12 in the assessment portion of the unit.

 

Phase Changes

There is a common misconception regarding temperature and phase changes. Many people believe that increasing or decreasing temperatures are responsible for phase changes in matter. While there is a temperature difference between solids and liquids or liquids and gases, it is not a difference in temperature that results in a phase change. Rather, it is the increase or decrease in the energy of the particles that results in a phase change. Applying or removing heat does cause a change in temperature, but it also causes a change in energy that is needed for phase changes.

For example, water freezes at 0 degrees Celsius but it also melts at 0 degrees Celsius. Anything below zero exists as frozen water, or ice. Anything above zero up to 100 degrees Celsius exists as liquid water. At 100 degrees Celsius, water boils or it condenses. Water above 100 degrees Celsius exists as water vapor (gas). Since the melting point and the freezing point occur at the same temperature, the change in energy is what determines whether the water will be a liquid or a solid. If energy is increasing, the result is liquid water. If the energy is decreasing, the result is ice.

Notice on the phase change diagram below that, at most places, both temperature and heat energy are increasing. But at the melting point and boiling point, only heat energy is increasing. It is the increasing kinetic energy among particles that initiates the phase change.

 

Image result for phase change diagram

 

The melting point is the point at which a solid will melt and turn into a liquid. The boiling point is the point at which a liquid will boil and turn into a gas. As a gas loses heat energy and condenses, it turns into a liquid. As a liquid loses heat energy and freezes, it turns into a solid.

Due to varying composition, each substance has its own unique melting point and boiling point. Therefore, the melting point and boiling point can be considered characteristic properties of matter. They are physical properties because melting, freezing, boiling, and condensing are all physical changes of matter.

 

When a solid gains enough heat energy at once to turn straight into a gas, this is known as sublimation. A good example of this is when snow on the ground turns to fog or water vapor without melting first. Another example is dry ice. It goes directly from a solid to a gaseous state in room temperature conditions.

 

Image result for sublimation

 

 

Now, take some time to explore the following PhET simulation on states of matter and phase changes.

 

 

States of Matter: Basics
Click to Run

 

Answer the following questions as you continue to explore the PhET simulation.

STUDENTS STATES OF MATTER BASICS DOCUMENT

 

Attach your completed States of Matter Basics document to question #13 in the assessment portion of the unit.

 

View the following video clip for more information on phase changes:

 

  The Changing Phases of Matter

 

Quizlet Vocabulary

https://quizlet.com/_3a0cij