LAB ACTIVITY- WHAT\'S OUT THERE?

When scientists attempt to determine the average composition of the
universe they face many challenges, primarily the inherent
\"clumpiness\" of the universe, or the face that the universe as a whole
is largely empty space punctuated by clumps of matter such as we see in
stars and galaxies. To make their estimate more representative, they
have to take the compositions of as many pieces of the puzzle as
possible and then take an average. Some of these samples can be analyzed
physically, but most of the matter in the universe is dispersed in
interstellar space and must be analyzed remotely by looking at the
spectra given off by the objects in question.

The following exercise is intended to allow students to calculate the
abundance of the elements in an imaginary universe. Each student pair
will be given a sample of matter from the universe to analyze.

Materials:

2 pound bag of white rice

2 pound bag of brown rice

1 pound popcorn

1 pound lentils

1 pound green split peas

1 pound yellow split peas

1 pound black-eyed peas

1 pound pea beans

1 large bag of assorted plastic beads

12-1 pint mason jars with covers (or other containers)

super glue

1 large basin

Procedure:

1\. In a large basin mix all materials except super glue.

2\. Fill each jar 1/3 full with mixture. Try to make jars if different
distributions.

3\. For 6 of the jars glue the covers with super glue after filling
them. Screw the tops on the rest of the jars, but do not glue them.

4\. Label the jars as follows:

2 open jars Stardust Mission Samples, 3 open jars carbonaceous
chondrite, 1 open jar Earth\'s atmosphere, 3 sealed jars super nova
spectra, 2 sealed jars interstellar spectra, 1 sealed jar the Sun
spectra.

Student Worksheet:

You have been given a sample of matter from some part of the universe.
Your job is to carefully analyze the contents of your sample and record
them in the data table below. If your sample cannot be directly observed
(opened) estimate the number of each element, and tell how you came up
with your estimate.

<table>
<colgroup>
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
</colgroup>
<tbody>
<tr class="odd">
<td>Element"</td>
<td>rice</td>
<td><p>brown</p>
<p>rice</p></td>
<td>popcorn</td>
<td>lentils</td>
<td><p>split</p>
<p>peas</p></td>
<td><p>split</p>
<p>yel. peas</p></td>
<td><p>black</p>
<p>beans</p></td>
<td><p>pea</p>
<p>beans</p></td>
<td>beads</td>
<td>total</td>
<td></td>
</tr>
<tr class="even">
<td><p># of</p>
<p>each</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>% of</p>
<p>each*</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>

\*%=# of each element/total x 100

1\. Which elements were the most common in your sample? (list the top
three)

2\. Record your results on the overhead and record the results of the
other jar\'s results on the data table below:

<table style="width:100%;">
<colgroup>
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
</colgroup>
<tbody>
<tr class="odd">
<td>Element</td>
<td>rice</td>
<td><p>brown</p>
<p>rice</p></td>
<td>popcorn</td>
<td>lentils</td>
<td><p>split</p>
<p>peas</p></td>
<td><p>split</p>
<p>yel. peas</p></td>
<td><p>black</p>
<p>beans</p></td>
<td><p>pea</p>
<p>beans</p></td>
<td>beads</td>
</tr>
<tr class="even">
<td><p>jar 1</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar 2</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>jar 3</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar 4</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>jar 5</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar 6</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>jar 7</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar 8</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>jar 9</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar10</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>jar11</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td><p>jar12</p>
<p>% of</p>
<p>element</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td><p>average</p>
<p>% class</p></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
</tbody>
</table>

Analysis Questions for Students:

1\. What elements do rice and brown rice represent? How did you
determine this?

2\. Why aren\'t all of the samples the same in elemental distribution?

3\. Why have certain jars been made inaccessible? What so the seeds in
these jars simulate in a real scientific attempt to determine the
composition of the universe?

4\. Compare the accuracy of determining the compositions of the closed
jars versus the open jars. What does this suggest about attempts to
determine the interstellar elemental composition versus the elemental
composition of actul physical samples?

5\. Why must we include sample of imstellar objects in our estimates of
the composition of the universe if they are not as accurate as the
physical samples?

6\. What could scientists do to make the estimate of the elemental
composition of the universe more accurate?

7\. How would the numerical elemental distribution in the universe
compare to the distribution by mass of the elements? Would it be the
same? Why or why not?