Classroom Activities

Additional activities, and expanded versions of these activities, complete with student worksheets, may be found at http://imagine.gsfc.nasa.gov/docs/educators/elements/.

 

GrandmaÕs Apple Pie

by Edward Docalavich Jr., The Heritage Academy, Hilton Head Island, SC

 

Carl Sagan is quoted as saying, "To make an apple pie from scratch you must first invent the universe." Working in groups, students create a presentation that illustrates the meaning of this statement. Each group selects an element that can be found in an apple pie and traces its evolutionary history back to the birth of the universe itself. Your discussion should address briefly the constant recycling of elements here on earth, as well as the formation of elements in the cores of active stars and supernovae. You must describe the way in which these elements were dispersed from the star through space and ultimately to the Earth. Include your vision of the environment in which that element may find itself 5 or so billion years from now after the Earth is long gone. Both your tracing of the element back through time and your creative vision of that element in the future should show a solid understanding of the "life cycle" of matter. Each presentation should be less than 15 minutes in length, and also include an artistic element Ð an original song, an illustration, a poem, a video, etc. that aides in explaining the scientific concepts you are trying to illustrate. Each presentation must show a solid understanding of the scientific concepts being discussed.

 

Cosmic Shuffle

By Minadene Waldrop, Terry High School, Terry, MS

 

In this card game, you will create the fusion reactions for elements up to oxygen. This game can be played with 2 or 3 players, and a separate score-keeper.

 

Preparation:  

Cut in half 3 x 5 note cards. On each resulting 3 x 2.5 card write the chemical symbols for the following elements and isotopes (the number in parenthesis indicates the number of cards of that element you will need.): 1H1 (24), 2H1 (3), e+ (7), e_ (3), energy (20), neutrinos (7), 4He2 (6), 3He2(5), 7Li3 (2), 7Be4(2) , 8Be4(1) , 8B5(1),12C6(3), 13C6(2) , 14N7(4), 15N7 (3), 15O8(3), 16O8(3).

 

Rules:

The game begins with each player being dealt 7 cards. The remaining cards are placed face-down as the stock. Players alternate turns where each selects one or more cards to make possible plays. During a playerÕs turn, the player forms one of the nucleosynthesis reactions (see list below), and places it on the table. The player uses cards in his/her hand, and those already on the table (using products of existing reactions) as input for new reactions. Reactions are mostly fusion, positron emission, and electron capture. The score-keeper records the points for the reaction. Points are determined using the mass of elements created in a reaction. Positrons, neutrinos, and energy are both worth one point. At the end of his/her turn, the player draws enough cards from the stock to again have 7 cards. The game is over when all cards from the stock are drawn. The winner is the person with the highest number of points.

           

Depending on the studentsÕ understanding of the nucleosynthesis reactions, an the scorekeeper can also serve as a judge to determine if the reaction actually occurs. Students may need to be reminded that when a proton changes into a neutron an electron or a positron is given off. Whenever an electron or positron is involved in a reaction a neutrino is given off. If a neutrino is given off it carries away the energy. If a neutrino is not involved then energy (gamma rays) are given off.

 

Reactions that can occur:

1H1 + 1H1 ˆ 2H1 + e+ + neutrino

(positron emission is when 1p +1 ˆ 1n0 + 0e+1)

2H1 + 1H1 ˆ 3He2 + energy (fusion)

3He2 + 3He2 ˆ 4He2 + 2 1H1 + energy

4 1H1 ˆ 4He2 +2 e+ + 2 neutrinos

3He2 + 4He2 ˆ 7Be4 + energy            

7Be4 + e- ˆ 7Li3 + neutrino    

(electron capture is when 1p1 ˆ 0e-1 =1n0)

7Li3 + 1H1 ˆ 2 4He2                              

7Be4 + 1H1 ˆ 8B5 + energy

8B5 ˆ 8Be4 + e+ + neutrino

8Be4 ˆ 24He2 + energy

12C6 + 1H1 ˆ 13N7 + energy

13N7 ˆ 13C6 + e+ + neutrino

13C6 + 1H1 ˆ 14N7 + energy

14N7 + 1H1 ˆ 15O8 + energy

15O8 ˆ 15N7 + e+ + neutrino

15N7 + 1H1 ˆ 12C6 + 2He4

 

 

Nickel-odeon

By Shirley Burris, Bayview Community School, Mahone Bay, Nova Scotia

 

This activity provides an auditory experience of the spectra of different elements.

 

Using colored paper, or a color print image of the colors in a rainbow, create a spectrum with the full range of optical colors. Cut this spectrum into strips, with each strip a slightly separate shade from its neighbor. Place these strips, one at a time, on the keys of a musical keyboard. The colors of the optical spectrum are now mapped onto the musical keys.

 

Now examine the line spectra of two or three elements. Below are the spectra for hydrogen, helium and oxygen. Note the location of the lines in the spectrum. What do these lines represent ? Why do different elements have a different pattern of lines ?

[insert illustrative spectra for H, He, and O]

 

For each spectrum, use strips of black paper to represent the spectral lines. Place these strips on the piano keys in the same position as in the spectrum for the element. Now, ÒplayÓ the chord that results from the markings, and ÒlistenÓ to the element.

 

Now create chords based on other elements. How do the elements sound differently ?

 

How is this model different from the true patterns of emission from the elements ?

 

(Color illustrations for this activity, and a full color spectrum to use on the keyboard, are available at http://imagine.gsfc.nasa.gov/docs/educators/elements/.)

 

Kinesthetic Big Bang

By Jeanne Bishop, Westlake High School, Westlake, OH

 

In this activity students will model the time after the Big Bang when the first nuclei of hydrogen and helium were created. The students will move and display cards that show the elements that are formed. The teacher should emphasize the need to be quiet and follow directions for this activity. Use a large area--an outside location, a large classroom with seats moved back, or a gym.

 

Materials Needed: Small cards or stiff paper (index cards or other) with p or PROTON printed on one side, and n or NEUTRON printed on the other side, in large letters, one for each student. Recall that for every 7 protons there is one neutron, although the number of neutrons may have to be increased if the class size is small. Also give each student cards individually marked DEUTERIUM (D = 2H), HELIUM 3 (3He), and HELIUM 4 (4He). These can be color-coded, for easiest identification. Two different, larger signs with 10 BILLION DEGREES K (or 10,000,000,000 billion kelvins or 1010 kelvins) on one and 1 BILLION DEGREES K (or 1 billion kelvins or 109 kelvins) on the other. One ping pong ball, held by the teacher. Make two cards, held by the teacher for BERILLIUM 7 (7Be) and LITHIUM7 (7Li).

 

Sequence:

1. To begin, students arrange themselves in a tight central group representing the matter that emerges in the first second, a soup of elementary particles. Students in the model represent parts of forces that will explode apart to become protons (p's or normal H nuclei) and neutrons (n's). Give one student the two temperature cards. Students have sets of cards with names or formulas: p and n, 2H, 3H, 3He and 4He.

Students hide all cards, since there are no elements before the Big Bang. If indoors, turn out the lights, representing the absence of electromagnetic energy before the Big Bang

 

2. When the lights are turned on, the teacher or a student calls "Big Bang." With this cue, the student inside the tight group with the temperature sign (10 BILLION DEGRES K) holds it up. Most students hold up PROTON card and a few hold up NEUTRON. Students start moving out from the dense center.

 

3. Some students should encounter (that is, safely bump) other students. For a while, the "particles" should not stick together.

 

4. The teacher gives the cue call of "100 seconds." The student with the temperature signs pulls away the 10 BILLION DEGREES K and sticks up 1 BILLION DEGREES K. Students hold the PROTON signs and continue to move outward. When two PROTONS meet, the two students decide if they want to bounce away or stick by holding hands (or locking arms) to form a deuterium nucleus. Then these students hide their PROTON cards and one displays a DEUTERIUM (2H) card. Couples representing deuterium continue bending and moving outward to encounter other PROTONS. Couples representing deuterium cannot stick to other single or couples of students until the next time cue is given. The reaction is: p + p -> D + positron + neutrino. Another way to get Deuterium is p + n -> D

 

5. If a DEUTERIUM bumps into a neutron and they join, HYDROGEN 3 is formed. The three students should hold hands (or lock arms) and exchange their cards for a 3H. The reaction is: D + n -> 3H

 

6. The teacher gives the cue call of "1000 seconds." The DEUTERIUM couples do not have to join to other single or couples of students when they bump. However, now students can join if they wish. For a DEUTERIUM sticking to a free PROTON, the three students should all hold hands, hide the DEUTERIUM and NEUTRON cards, and show a HELIUM (3He) card. The reaction is: D + p -> 3He

 

7. Following formation of 3He, if an 3He joins another 3He, only four of the six students should hold hands, hide the DEUTERIUM cards, and show a HELIUM 4 (4He) card. Two of the students who were part of the 3He's should leave the HELIUM 4 group and hold up their original PROTON cards. (Note: Students may want to stick more often that what correctly models the early universe.) The reaction is 3He + 3He -> 4He + p + p Other possible reactions to produce 4He are: 3He + D -> 4He + p; 3He + D -> 4He + n + positron; 3He + n ->4He         

 

8. The teacher directs one of the remaining HELIUM 3 (3He) join with an HELIUM 4 (4He) and give them the BERILLIUM 7 (7Be) card and a ping-pong ball representing an electron. First this group should hold up the BERILLIUM 7 (7Be) card, then throw out the ping-pong ball. Then they should hide the BERILLIUM 7 card and hold up the LITHIUM 7 (7Li) card.

 

9. The teacher gives the cue call of "End". Students freeze in position with signs up so that all can see what has occurred. Ask students if what the model shows is the correct ratio of nuclei from element formation in the Big Bang (90 percent total H and 10 percent total He with almost no free neutrons). Probably the outcome will be wrong. Ask students what can be done to make the H to He ratio correct. Students probably will need to split some nuclei. Discuss who should split and then do it. Student with the temperature card pulls it down, indicating a further cooling of the universe.

 

Follow-up questions (while still in model positions or later)

1. What is wrong with "freezing" the motion at the end of the activity?

 

2. How are the numbers of particles and atoms we have formed different from what really occurred?

 

3. Why can't the groups keep combining like they did in this activity to form all the elements heavier than hydrogen, helium, and lithium?

 

4. Since the atoms are moving, what caused the atoms to clump together to form stars, quasars, and galaxies

 

An extended version of this activity, with student worksheets, is available at

http://imagine.gsfc.nasa.gov/docs/educators/elements/.

 

 

Elemental Haiku

By Kim Cochrane, Bowie High School, Bowie MD

 

A Haiku is a poem with a certain rhyming pattern. The Haiku pattern has three lines - the first line has five syllables, the second line has seven syllables, and the third line has five syllables. For example,

 

            Projects left undone,                                        Pi - ratio of

Nobel prizes never won-                                  Around: across a circle -

            buried messy desk.                                          An endless number?

- Stuart Henderson                                        - Anonymous

 

 

Brainstorm topics that concern the cosmic origin of the elements and write them on the chalk board. Have students work independently to write at least one 3-line Haiku. The Haiku's topic must be something that is on the board from the class brainstorm. Have the students write their Haiku as large as possible on 8.5 x 11 paper so that it can be displayed. Encourage students to accompany their poem with a picture. When completed, have students read their Haiku to the class and discuss the information within it. Display the Haikus on a wall or bulletin board.

 

 

Cosmic Ray Collisions

By Shirley Burris, Bayview Community School, Mahone Bay, Nova Scotia

 

This activity models cosmic ray collision. Tennis balls represent the cosmic rays, and a Velcro target represents the point of collision. The purpose of the activity is to enable students to internalize an appreciation for the probability of collision of particles.

 

Students will use the tennis balls to attempt to hit a target, in order to:

1. Determine the probability that the tennis balls will hit

a.     The target

b.     One another at the target spot

2.     Record percentage of strikes of balls thrown.

 

Once the data is collected, conversation about collision of cosmic rays can take place. Discuss the size of the tennis balls, the size of the room, and distance thrown, with respect to the probability of collision. Compare to size of cosmic rays, and distance traveled, to internalize the concept of collision of cosmic rays. The activity gives a Òjumping offÓ point for students to begin to think about the size of the universe, the size of the particles involved in cosmic ray collisions. Students will see the difficulty experienced in getting single tennis balls to hit the target, and the greater difficulty in orchestrating the connection of more than one at target point. They can then reason that if this level of difficulty is reached with objects the size of tennis balls in a small area such as the classroom, then the probability of objects the size of cosmic rays, over distances even as ÒcloseÓ as the Sun, will be very low.

 

Procedure

Students will need 3-6 tennis balls. The tennis balls can be used Òas isÓ or can be wrapped in Velcro strips. A 3Ó x 5Ó strip of Velcro can be taped to a spot on the wall in the classroom. Students will place themselves at the opposite end of the classroom for purposes of throwing the tennis balls. Care should be taken to clear the path of the tennis balls, and to instruct students to throw with reasonable care.

 

First they will be invited to throw 3-6 tennis balls to the target across the room. Students will try this first with one ball from varying positions, and then with two, or three, requiring that all balls hit the same target at the same time.

 

Students will be invited to predict the probability of a ÒhitÓ in all instances; will discuss factors involved in the success or failure of hits to occur, and will discuss and record the rate of hits, and outcomes related to position and number.

 

Students will compare the tennis ball size and distance thrown to the size of cosmic rays and distance traveled.

 

 

Cosmic Abundances

A. Refer to the chart of the solar system abundances on page XXX. From the plot, answer the following:

 

What is the abundance of hydrogen ? of helium ? of aluminum ? of gold ?

 

How much more hydrogen is there in the solar system than helium ?

How much more hydrogen is there than oxygen?

How much more hydrogen is there than gold ?

 

B. Below is a table of the various processes that create elements, along with the abundance of the predominant elements it creates.

 

Process                        Predominant elements             Abundance

BigBang                      H, He                                       1.10 x 1012                  

Small Stars                  C,N,O                                      1.19 x 109       

Large Stars                  other elements up through Fe  2.58 x 108                   

Supernovae                  elements beyond Fe                 7.96 x 104                   

Cosmic Rays               Li,, Be, B                                  2.68 x 103                   

 

What are ways to illustrate or plot these data?

 

 

WhatÕs Out There

Based on an idea by Stacie Kreitman, Kilmer Middle School, Falls Church, VA

 

This exercise allows students to calculate the abundance of elements in different substances.

 

Materials and Preparation:

Each element is represented by a different food found in a kitchen. Below are suggested items for different elements. Different colored candy sprinkles also work well. Each item should be approximately the same size.

 

H - White Rice           He - Green Split Peas             O - Brown Rice

C - Black Beans          Fe - Red Lentils                       N- Brown Lentils

Ar Ð Blue Sprinkles     Si Ð Pearl Barley                     Mg Ð Wild Rice

 

Prepare mixtures of these items according to the following recipes. Note that these abundances are by number, not weight. So measure using dry measure, not a scale.

Below are listed the percentages, and the amount of each element for a total of 10 oz for each substance (Note that the percentages may not add to 100% due to our excluding less significant elements.). Place each into a separate jar or bottle. (11 oz. plastic water bottles work well). Cap all the jars/bottles. Seal some of them using superglue, but leave others that can be opened.

 

[1/8 cup = 10%, 1 tsp = 1 %, measurements to be checked with Suzanne]

Carbonaceous Chondrite         Supernova                               Human Body

O         44.3%  1/2 cup            O         42.2%  1/2 cup            H         61.6%  3/4 cup

H         30.8%  1/3 cup            Fe        36.7%  3/8 cup             O         26.3%  1/4 cup +

Mg      6.2%    6 tsp                C         11.1%  1/8 cup             C         10.0%  1/8 cup

Si         5.5%    5 1/2 tsp          Si         3.7%    3.75 tsp           N         1.5%    1.5 tsp

Fe        4.9%    5 tsp                Mg      2.8%    2.75 tsp

C         4.2%    4 tsp

 

The Sun:                                  EarthÕs Atmosphere:

H 92.1%     1 1/8 cup         N         78%     1 cup

He 7.8%     7 3/4 tsp          O         21 %    1/4 cup

                                                Ar        1 %      1 tsp

 

 

Procedure

Give the bottles to the students, with each pair of students working on one bottle. Also give them a copy of the key as to what element each type of object represents. Have the students estimate the composition of the bottles by giving the fraction of hydrogen, fraction of helium etc., Note that students with bottles that can be opened can directly sample the material, but those with sealed bottles must estimate visually.

 

Now give the students the abundances for the different objects. Have the students determine what type of object their bottle represents. You may choose to leave the Human Body off the list and treat it as a Òmystery.Ó The students should determine what it could be.

 

An extended version of this activity may be found at http://imagine.gsfc.nasa.gov/docs/educators/elements/.