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Educator Guide: States of

This document is a resource for teachers whose classes are participating in the Museum of Science’s States of Matter Program. The information in this document may be used as a classroom resource and/or as background information for the teacher concerning the subject of the states of matter.

Table of Contents:

Vocabulary List……………………………………………………………………………2

Further Background Reading…………………………………………………………...6

Suggested Classroom Materials……………………………………………………... 7

Activity Description………………………………………………………………………8

PowerPoint Description………………………………………………………………… 9

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Vocabulary List

This is a list of common terms that teachers may wish to be familiar with for the States of Matter program. This list is also a suggestion of vocabulary for students attending the program to learn, though prior study of these words is not required for student participation.

Air – the collection of breathable that makes up the lower portion of the ’s . The main components of air are Nitrogen (78%), Oxygen (21%), and other trace gases (1% ‐ Aragon, , Neon, , etc…).

Boiling – the transition from a to a . is a much more energetic process than and happens throughout the liquid, not just at the surface. Boiling only occurs when a substance has reached its .

Celsius – the unit of measurement for the most common scale used throughout the world today. This is the temperature scale also used frequently by scientists.1

Condensing – the transition from a gas to a liquid. The temperature at which this change occurs is called the point.

Cryogenic – any liquid that exists at a really low temperature. The table below lists the properties of a variety of elements that form liquids at very low . Although it is not a cryogenic liquid, is also listed for comparison:

Element Freezes/Melts Condenses/Boils Freezes/Melts Condenses/Boils Water (not an 32 212 0 100 element but a ) Xenon -169 -162 -112 -108 Argon -310 -302 -190 -186 Nitrogen -346 -320 -210 -196 Oxygen -362 -297 -219 -183 Neon -416 -410 -249 -246 Hydrogen -434 -421 -259 -252 Helium -454 -452 -270 -269

1 The original Celsius scale was based on two significant temperatures related to water: its point was assigned as 0°C and its boiling point became 100°C.

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Cryogenics – the science of extremely low temperatures, typically well under ‐ 50 ˚ Fahrenheit

Density – a measure of how closely packed together the and of a substance are. Density = / . A less dense material will always float in denser material (like wood in water or helium in air).

Dry – the form of Carbon dioxide (CO2)2

Evaporating – the process when the surface of a liquid transforms into a gas. Evaporation is a gradual process and can happen at any temperature even at temperatures below a substance’s boiling point.

Farenheit – the temperature scale that is used in the United States and a handful of other countries. Unlike the Celsius and scales, the Fahrenheit scale does not use the chemical properties of different substances as reference points.

Freezing – the transition from a liquid to a solid. The temperature at which this change occurs is called the freezing point.

Gas – a that does not have either a definite shape or a definite volume. Gases will expand to take up the shape and volume of their container.

Heat – a flow of thermal from one system to another due to a difference in temperature

Kelvin – a temperature scale that is often used for very or very hot substances. The Kelvin (there is no degree marker used) is based on an absolute temperature scale where (see definition) is defined as 0 Kelvin.

Liquid – a state of matter that has a definite volume but not a definite shape. Liquids flow easily and take on the shape of their container.

Mass – a measure of the amount of matter in a substance or material

2 At standard , carbon dioxide will transform from a gas to a solid at -78°C or -109°F. This process of transforming from a gaseous state to a solid state is called deposition. The reverse (solid to gas) is called sublimation. does not occur naturally on Earth because of the low temperatures involved, but any substance colder than -78°C (including ) can be used to change carbon dioxide gas into a solid.

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Matter – anything that has mass and volume. All objects in the visible are composed of matter.

Melting – the transition from a solid to a liquid. The temperature at which this change occurs is called the point.

Molecule – a grouping of at least two atoms held together by chemical bonds. Water is an example of a molecule (H2O ‐ 2 hydrogen atoms bonded to an oxygen ).

Nitrogen – an element that is the main component of the Earth’s atmosphere (about 78%) and is found bonded to other elements in various compounds found here on Earth. We use nitrogen in its liquid form during the program and as a liquid it is clear and colorless.3

Plasma – a state of matter that is composed of ionized gas. An ionized gas is a gas which has lost (negative charges found in the atom). Although plasmas are rare on Earth ( is an example), it is the most common visible form of matter found in the universe. The Sun and other stars are made of .

Pressure – the amount of force (push or pull) acting on a given surface area. Pressure = force/ area. The greater the force acting on a surface, the greater the pressure. The liquids and gases that we use in the program all exert pressure on their containers.

Solid – a state of matter that has both a definite shape and a definite volume

States of Matter (or Phases of Matter) – the physical forms of matter. Here on Earth the most common states of matter are , liquids, and gases. Plasma is much rarer on Earth but is found almost everywhere else in the universe. A variety of additional states of matter also exist, but they form under extreme conditions and often need to be created in the laboratory.

3 The boiling point of liquid nitrogen is -196 °Celsius, -320 ° Fahrenheit, or 77 Kelvin so nitrogen must be at this temperature or lower to exist in its liquid from. These temperatures are too low to exist naturally on Earth, so liquid nitrogen must be manufactured.

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Superconductor – a material that under the right conditions can act as a near perfect conductor of electricity4

Temperature – a measure of the relative hotness or coolness of a substance. The temperature as measured by a thermometer is really a measure of the average moving energy () of atoms and molecules in a system. Note that this is a subtly different idea than simply measuring how much is in a substance.

Thermal Energy – the energy associated with the random motion of atoms and molecules

Volume – the amount of space that a solid, liquid, gas, or plasma occupies

4 A few materials can become superconductors when they reach a low enough temperature. The superconductor we use in the program is a manmade . Using liquid nitrogen, we are able to cool the disk below the needed temperature. When such a material becomes a superconductor, there are two main effects. First, a superconductor is a perfect conductor of electricity. Second, the material will push away all magnetic fields. It is this second property that allows us to repel and levitate a small above our superconducting disk. But once the temperature of the disk goes back up, it stops being a superconductor and the magnet falls back down.

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Further Background Reading

This is a suggested reading list for teachers looking to improve their understanding of the states of matter, as well as a resource for classroom ideas on the subject.

Curricula

Changes of State – Insights: An Elementary Hands-on Inquiry Science Curriculum by Educational Development Center, Inc. Kendall/ Hunt Publishing Company. Dubuque, IA. 2003.

Inquiry in Action: Investigating Matter through Inquiry by James H. Kessler and Patricia M. Galvan. American Chemical Society. Also available for free online at: http://www.inquiryinaction.org/

Links

PBS NOVA: Absolute Zero Website – http://www.pbs.org/wgbh/nova/zero/

American Institute of : – http://www.aip.org/history/mod/superconductivity/

Rader’s Chem4Kids: States of Matter – http://www.chem4kids.com/files/matter_intro.html

Exploratorium: Outrageous Ooze (make a very interesting material called oobleck in the classroom and try and classify its state of matter) – http://www.exploratorium.edu/science_explorer/ooze.html

Collaborative Learning: States of Matter Card Games – http://www.collaborativelearning.org/statesofmatter.pdf http://www.collaborativelearning.org/changingstates.pdf

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Classroom Materials

Below are some suggestions for books, videos, and websites to help students increase their understanding of the states of matter.

Books

Matter – Eyewitness Books by Christopher Cooper. Dorling Kindersley Publishing, Inc. New York, NY. 2000.

The Story of Nitrogen by Karen Fitzgerald. Franklin Watts. New York, NY. 1997.

States of Matter – The Library of Physical Science by Suzanne Slade. The Rosen Publishing Group, Inc. New York, NY. 2007.

States of Matter by Robert Snedden. Heinemann Library. Chicago. 2001.

Videos

Absolute Zero (DVD). PBS NOVA. 2008. Also available to watch online: http://www.pbs.org/wgbh/nova/zero/program.html States of Matter by Robert Snedden. Heinemann Library. Chicago. 2001.

Links

PBS NOVA: Absolute Zero Website (activities, interactive, games, and more) – http://www.pbs.org/wgbh/nova/zero/

NASA Jet Propulsion Lab: Temperature Scales – http://funphysics.jpl.nasa.gov/adventures/temperature-game.html

Rader’s Chem4Kids: States of Matter – http://www.chem4kids.com/files/matter_intro.html

BBC: Activities and interactives – http://www.bbc.co.uk/schools/ks2bitesize/science/materials/ http://www.bbc.co.uk/schools/ks3bitesize/science/chemical_material_behaviour/b ehaviour_of_matter/activity.shtml http://www.bbc.co.uk/schools/ks3bitesize/science/chemical_material_behaviour/p article_model/activity.shtml

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Activity Description

See the “Documents” section on the website to download this activity.

Making

In this activity, students will make ice cream by lowering the temperature of their ingredients below the freezing point of water. As an extension, students can also explore more about the transfer of heat energy using an ice cube.

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PowerPoint Description

See the “Documents” section of the website to download this PowerPoint PDF.

States of Matter

These slides show the various transitions among the three most common states of matter found on Earth: solids, liquids, and gases. We also show the relative temperature of water in its various forms and nitrogen.

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