States of Matter

The students are asked by Dogleg Travel Association to create a pamphlet about Mount Karmit. As they climb up the students discuss how boiling points change for cooking and how the thin atmosphere can cause medical problems for some climbers.

See Instructor’s Notes below:

Instructor Notes

This document was prepared to assist case instructors and mentors with the facilitation of case teaching and learning with the LOGgED ON science curriculum.� The materials included reflect a variety of resources for teaching the designated case.� First, potential student activities are contained in this document.� Second, supplemental resources such as complimentary web sites are provided also.� References to the general science knowledge and skills covered by each case similar info is provided for instructors, mentors, and students under the ï¿½Professor Powers� Notebook� section of the case site.�

 

CASE RELATED STUDENT ACTIVITIES

 

Discussion Questions

  1. What is the difference between the elements on the Period Table of Elements?� How do they differ by row?� By column?
  1. Has the idea of what an atom �looks like� changed?
  1. Can a substance be a compound and not a molecule?
  1. What common substance can exist in three states (solid, liquid, gas) at one time?
  1. What is that point of coexistence is called?
  1. Why do plasmas occur more commonly in outer space?
  1. What does a bathroom scale measure: mass or weight? Why?

Activities

  1. Does a liquid exist that is denser than a solid?� If so, what is an example?
  1. If you double a cube�s dimensions (length, width and height), by how much does its volume increase?

INSTRUCTOR DEMONSTRATIONS

 

  1. North Carolina State University States of Matter Demos for Elementary and Middle Schools http://www.ncsu.edu/ncsu/chemistry/outreach/states_of_matter.html
  1. Examples of chemical changes are burning wood, cooking & baking, freezing water, rusting, and moldy bread.� Any of these changes could be demonstrated for the class.
  1. Build A Carton Atom

http://www.pbs.org/wgbh/aso/tryit/atom/

CASE RELATED WEB SITES

 

EXPERIMENTS

 

Changing Physical States of Matter Experiment/Laboratory http://www.iit.edu/~smile/guests/chgstate.htm

Two Experiments with Fluids

http://www.school-for-champions.com/science/experiments/expmatterstates.htm

 

TEACHING RESOURCE SITES

Solid, Liquid and Gaseous States of Matter: Review

http://www.school-for-champions.com/science/matterstates.htm

Student Friendly Information

http://www.chem4kids.com/files/matter_states.html

 

Explanations and Heat Curve Math Problems

http://www.chemtutor.com/sta.htm

States of Matter Vocabulary

http://www.ccl.net/cca/documents/dyoung/topics-orig/states.html

Glossary of Terms

http://members.tripod.com/~EppE/pc1term.htm

Online Simulations

http://polymer.bu.edu/vmdl/Curriculum/RedBook/SL1.html

See Professor Power’s glossary of terms (referenced throughout the case) below:

Science at High Elevations

As the sun makes its way through the hotel room curtains, Emma stretches out her arms above her head. The warm sunlight hitting the window signals another beautiful day on Dogleg Island. She looks over to the bed next to her, expecting to see her roommate Crystal still asleep, but notices that the bed is empty. Instead of sleeping, Crystal is hovering over the stove in the small kitchen to Emma’s left, boiling water for her favorite morning food – a hard-boiled egg as well as pancakes for Emma.

“That smells wonderful, Crystal,” Emma says, still rubbing the sleep from her eyes.

“Oh good, I’m glad because you’re going to have to help me eat these,” she responds, pointing down at the bubbling pancake batter. “I’ve really missed being able to cook like I used to back home. This dinky kitchen isn’t much, but at least I can make some breakfast. I’ve noticed that it’s taking me longer to cook my hard-boiled eggs here than it does back in Los Angeles. It probably has to do with the elevation difference between here and L.A. We are in the foothills of the Batten Mountains, so we’re at a higher elevation than back in southern California. At higher elevations, the temperature at which water boils is lower, therefore, because of this lower temperature it actually takes longer for food to cook.”

“You know, now that you mention it, I think I remember hearing that before,” Emma says. “That’s some pretty interesting stuff.”

Crystal and Emma sit down to eat their breakfast together as the food finally is finished cooking. They get their things ready for a day trip to the Batten Mountains, today’s destination for Professor Powers and her students. The girls will need the energy from the food for their hike up part of the highest mountain on the island.

“The Mountain Matters”

Snow-capped mountain

An hour later Crystal and Emma join Professor Powers and the rest of the gang outside in front of the hotel. Within another hour, they arrive at the foot of Mount Karmit. The students stare up at the mountain in amazement at the majestic landmark. At a height of 12,324 feet, Karmit towers over the smaller mountains in the range surrounding it. Emma in particular is in awe of the mountain’s magnificence given that her home is in Nebraska, one of the flattest parts of the United States. She’s especially puzzled when she looks up to the mountain’s peak and notices that the mountain is snow-capped.

“I thought it was too warm to have snow around here,” Emma thinks aloud.

“Yes, Emma,” Professor Powers responds. “You’ve touched on something that we’re going to be thinking about today. Besides having some fun hiking up the mountain, we’re also going to help the Dogleg Travel Association create a pamphlet about Mount Karmit. Even though this brochure is going to provide advice for backpackers and hikers interested in taking on this mountain, it’s inevitable that some science will enter into it, too. For example, we must come up with an answer to your question and others like it for future tourists. Let’s move up the mountain.”

The group unloads the van and hoists their gear onto their shoulders. They realize that the trek up the mountain will be a long and arduous one, but the students seem up to the task.

“Isn’t it amazing that huge mountains like this can exist?” Crystal says, just as amazed as Emma at the mountain’s stature. “I mean, when you break everything down, all matter is made up of atoms. It’s hard to believe, when you look at Mount Karmit that at its simplest form it is just atoms. In fact, it is made up entirely of atoms. It blows my mind.”

“It’s not that simple. Karmit is made up of rocks, dirt, trees and shrubs– not atoms,” Dimitrius interjects as the group members begin their ascent up the mountain.

“Yeah, but what do you think all rocks, dirt, etc. are made up of……Atoms!” Crystal retorts. “Professor Powers, would you please set Dimitrius straight?”

“You know, Dimitrius, Crystal is right. This is her area of expertise. Atoms are the building blocks for all matter. And all atoms, regardless of state, have mass.”

“Professor Powers, what do you mean by ‘state’?” Peter asks.

Professor Powers tries to explain. “States of matter changes occur when a material changes from one form of to another,” she explains. “There are four states of matter– solid, liquid , gas and plasma.”

Neon lights

Professor Powers continues, “Plasma, isn’t one state of matter that you need to be too concerned about for the purposes of our studies on Dogleg Island. Plasma mostly occurs in outer space rather than here on Earth. However, a good analogy is that plasma is like the stuff inside neon signs – the glass tube of the sign is filled with a gas, usually neon, and there is electricity running through it. As the electricity moves through the gas, the gas glows, creating the plasma.”

“So, to change from one state to another, the atoms within a substance have to undergo a chemical change?” Billy asks quizzically.

“No,” adds Crystal. “Phase changes are by definition physical changes. You can cause a physical change by adding energy to a substance by increasing its temperature or its pressure, or by decreasing energy by decreasing temperature or pressure.”

Click here to view the different behaviors of gases, liquids, and solids.

“Do you all understand why changing temperature or pressure could potentially cause a change in the state of matter?” Professor Powers asks her students.

“I think I remember learning in my science class last year that volume and pressure are related,” Billy says. “If I remember correctly, volume is the amount of space that an object fills up. And pressure is how much force an object exerts on a surface.”

“My teacher taught me that when the particles of an object are moving around at faster speeds, the pressure increases because the particles are pushing out on the container’s walls with greater force,” Dimitrius adds to Billy’s comment. “So, if you want to increase the pressure of a gas, for example, you would actually have to decrease the volume. Volume decreases when the particles become more compact. When you do this, the gas particles collide with one another more and hit the walls of the container with greater speed.”

A diagram illustrating the volume and pressure relationship of gases.

“That’s a pretty good summary, Billy and Dimitrius,” Professor Powers commends the two.

Professor Powers explains this phenomena to her students (the diagram illustrates her point). “When the volume of gas particles is small, the pressure of the gas increases. This is an example of Boyle’s Law. Therefore, the more condensed the particles the greater the pressure of the gas.”

Boyle’s Law:

“But did you know that temperature is actually the average energy of motion of the particles that make up a substance? So as the pressure of the substance rises, so does the temperature, ” continues Professor Powers. “Temperature remains relatively constant during a phase change because of the transfer of a large quantity of latent heat to the surroundings produces a broad plateau of nearly constant temperature, “ she adds. “Let me give you an example. When ice melts, the molecules move around, rearranging themselves, but the molecules’ themselves do not slow down or increase speed. This explains why the temperature of ice stays at 0degrees Celsius. When water boils the temperature stays at 100 degrees Cesius. Why?”

Temperature:

A diagram illustrating thermal heating.

“I know the answer Professor Powers,” interjects Crystal. The water molecules do not move any faster when boiled, so the temperature stays the same.”

“That’s right, Crystal,” Professor Powers replies.

Realizing that the students have had a lot of new information to think about while hiking the steep incline of the mountain, Professor Powers realizes that it is time to take a snack break.

“The Effects of the Elevation”

As the group finds a set of rocks to rest on while they take their short break, Professor Powers takes out six sandwich bags full of trail mix that she brought along for herself and her fellow hikers. Crystal grimaces as Professor Powers hands her one of the bags.

“I really don’t like this stuff very much,” she says. “I would much rather just have a sandwich.”

“Well, logistically, it’s a little more difficult to bring bread and deli meat along with us,” Professor Powers explains. “Even though our journey won’t bring us close to the top of the mountain today, I thought you all should experience a little bit of what it’s like to be a true mountain climber. People do not realize how much science can be learned and is involved in hiking steep inclines.”

Peter exclaims. “I can’t believe how much my ears hurt! I can hardly hear anything you just said, Professor Powers”

“Oh Peter, you’ll be fine,” Crystal says. “My ears have been popping since we began climbing, too. It’s totally normal, so do not worry.”

As Peter and Crystal finish their snacks, Professor Powers decides that it is time to show the students the many ways in which air pressure comes in to play during mountain climbing. A good teacher does not miss any chance to teach something new. “Can anyone explain why Peter and Crystal’s ears have been popping?”

“Oh, I’ve been feeling that, too,” Emma says. “Right now my ears feel the same way they do when I fly in a plane. I think it has something to do with being at a higher altitude.”

“Yeah, doesn’t it have to do with how air pressure changes when you move up to a higher altitude? I think air pressure decreases the higher up you go,” Billy asks. “I’ve read about ‘cabin pressure’ in the airplane and how it changes when the plane leaves the ground and begins to climb up into the air. A saw an article just recently about passengers being injured from changes in cabin pressure.”

“Yes Billy, you’re right, air pressure decreases at higher altitudes,” Professor Powers responds. She is pleased to see that the students are beginning to figure out some of these scientific questions on their own. “Because of this change, your ears have to adjust as well. As your body tries to adapt to the difference in pressure, it equalizes the pressure inside your ear with the pressure outside your body. When this happens, your ears pop, which can get annoying.”

“I’ve never understood why air pressure would be lower the higher-up you climb,” Dimitrius questions. “It seems like it would make more sense for air pressure to be higher at higher altitudes, wouldn’t it?”

A diagram illustrating air pressure.

“I think I know what you mean, Dimitrius,” Crystal affirms. “But what you need to do is think of the example from the ocean to help you understand air pressure. When you dive below the water’s surface, the farther and farther down you go you notice that the pressure increases, right? That’s because there is so much water above you. You need to think about air the same way. When you’re on the ground at sea level, air pressure is the highest because you have so much air above you. But as you move higher up a mountain, there is less air above you. It’s like being closer to the top of the sea of air.”

“Well spoken, Crystal,” Professor Powers says. “I really like the ‘sea of air’ comparison. Another way to look at this situation is to remember that as you move up to higher elevations, the air becomes thinner. This means that the density of air decreases, and therefore the pressure of air decreases as well. These changes in air pressure have tremendous implications for mountain climbing, as I think you guys are beginning to understand.”

“Hey, how does the drop in air pressure result in snow on the top of the mountain? How does the temperature and change in temperature interact?” Emma asks.

“Yeah, isn’t the air closer to the ground warmer because the ground is warm, but the higher up you move, the cooler the air becomes,” Crystal responds.

“You are both thinking along the right lines,” Professor Powers says. “As you move higher, not only does the air pressure decrease, but the air gets cooler as well. When this air contains moisture, it will often condense and form either rain or snow depending on the temperature. We’ve already got a lot of stuff to think about for our brochure. If we’re all ready, why don’t we collect our trash and keep on with our hike?”

“The Effects of Elevation” cont.

Now a couple hours later, the group has made its way to the 3,000 feet elevation point. Here they run across a mountain climber’s camp, with several groups of hikers taking some time to relax and reorganize their supplies. Professor Powers recognizes one of the hikers as a college roommate and decides to go introduce her old friend to her students.

“Hey Susannah, how are you doing? What brings you here today?” she asks her old friend as she gives her a hug.

“Marisa? Is that you? Wow, I wouldn’t have thought of running in to you here!” Susannah responds, excited and surprised to see her old buddy. “I’m actually here with a few people I’m training with. We’re working our way up to tackling Mount Everest in a few months, but before we do that, we thought we’d get ourselves ready by climbing some smaller mountains.”

Mount Everest

The students’ eyes become wide when Professor Powers’ friend mentions Mount Everest. They realize that at 29,035 feet, Everest is the tallest mountain in the world. The extremely high elevation makes climbing the towering mountain quite a feat. In the last 80 years, about 170 people have died in their attempt, or about one in every eight who have tried to climb it. The students think Susannah must be pretty brave.

Susannah looks over to some of her hiking companions who are busy boiling water over a small fire they had started. “My fellow climbers decided that they wanted to cook food today to practice cooking at higher altitudes. We’ll be eating a lot of oatmeal when we go on the real trip!”

“What do you mean when you say you’re practicing cooking food at higher elevations?” Peter asks.

“Oh, I know what she means,” Crystal interjects. “I experienced some problems with cooking at high altitudes this morning when I was trying to cook breakfast. I noticed that since our hotel is in the foothills and at a higher elevation than my home back in L.A., it actually took longer for my hard boiled egg to be ready. Emma and I were talking about it. We concluded that at higher altitudes water boils at a lower temperature, therefore, you have to increase cooking time for proper food preparation.”

Click here to learn more about a liquids boiling point.

“That’s right – a liquid’s boiling point depends on the air pressure above the liquid,” Professor Powers explains. “We’ve already talked about how air pressure decreases as we move up the mountain. As air pressure decreases, water molecules need less energy to escape into the air. That’s why water can boil at a lower temperature the higher you travel. Remember that as water boils, some of the water turns into water vapor, or gas.”

“Mountain Sickness”

As the group discusses how changes in air pressure at high altitudes affects cooking, Billy spots two men walking toward Susannah. One of the men is leaning on the other for support, and Billy approaches the men to see if he can be of assistance. The men explain that they have come down from the summit to get Susannah’s help. Just then Susannah walks over to her two friends.

“Oh no, did Scott have difficulty acclimatizing to the higher altitude?” Susannah asks, referring to the man leaning on the second man for support.

“Yeah, Scott was having some trouble as we got up to the summit today,” his friend James explains. “His body wasn’t prepared to handle the change in the amount of oxygen available at over 12,000 feet above sea level. He was trying to get up the mountain too quickly.”

Emma notices the commotion and overhears the conversation. She pulls Professor Powers to the side to ask her about the situation. “I don’t understand how climbing a mountain too fast could make someone sick. Did Scott just not eat enough food so he didn’t have enough energy?”

“Diet could have something to do with it,” Professor Powers responds. “But more likely what his friend James is talking about relates to the drop in air pressure at high altitudes that we have been discussing today. Most of the time, when people travel above an altitude of 8,000 feet, they risk altitude sickness. Three of the most common results of maladjustment to high elevations are acute mountain sickness, high-altitude cerebral edema, and high-altitude pulmonary edema.”

Emma and Professor Powers return back to listening in on the other conversation.

“I think…I climbed…too quickly,” Scott says, taking very short breaths between his words.

“You definitely didn’t give yourself time to acclimatize,” James reminds his friend. “I was pretty worried about you for a while there. We’re definitely not like the Sherpa people of the Himalayas. It’s a good thing we got you down to a lower elevation when we did.”

“It’s an unfortunate way to learn this lesson, but mountain sickness is nothing to take lightly,” Susannah chimes in. “I want everyone to understand the symptoms and how to appropriately deal with the affects of these illnesses before we begin our trek up Everest in a few months.”

Crystal notices the group gathered around Scott and walks up to the crowd to see what’s happening. “I guess you didn’t think of taking an oxygen tank along with you, since the peak of Mount Karmit is only a little over 12,000 feet high.”

“An oxygen tank?” Billy asks with a confused expression on his face. “Why would they need an oxygen tank?”

“Well, as you move up in elevation, the air becomes less dense,” Susannah explains. “Less dense air contains less gas. The air we breathe is about 21 percent oxygen. So, as the air contains less gas, one of the primary gases depleted is oxygen. When climbers bring along oxygen tanks, they can avoid having to breathe more vigorously as they would otherwise have to do without supplemental air.”

“It doesn’t seem like oxygen tanks would do much good,” Billy says. “A 30-pound tank of oxygen doesn’t sound like it could last that long. I can’t see how you could store much oxygen in there.”

“Billy, you’re forgetting what we were talking about earlier today about gas,” Crystal reminds him. “Remember that gases are disordered, and that they can change volume easily. This means that they also are easy to compress. A lot of oxygen can fit inside a 30-pound oxygen tank because the oxygen molecules can be made very compact. So, the pressure inside an oxygen tank is pretty tremendous.”

“I think I get what you’re saying,” Billy responds. “It’s kind of like a helium tank. One tank can be used to inflate a whole lot of balloons.”

“Good thinking, Billy and Crystal,” Susannah commends the pair. “It looks like James and I better work on getting Scott all the way down to the bottom of the mountain just to make sure that everything is okay. It has been really great meeting all of you. I hope to see you soon, Marisa.”

Professor Powers says goodbye to her old friend and the she gathers her students to begin their decent of the mountain. She notes, “Since Scott is an experienced climber, and he had trouble breathing higher up on Karmit, I don’t think we should go any farther.”

After the group returned to the van in the parking area Professor Powers wraps-up the experience with her students. She comments, “I think you all have had a chance to learn about mountain climbing and what climbers need to consider before beginning an expedition. The science of states of matters plays an important role in understanding safe mountain climbing. What are the significant issues to consider? What different perspectives exist regarding safe climbing? What are ‘safe’ strategies for healthy climbing?”

The professor indicates that its time for the students to decide what information to include in a brochure for tourists that clearly outlines the science of ‘safe’ mountain climbing.