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    Outreach and Education Division

    The EDUCATION AND OUTREACH DIVISION supports chemistry education at all levels, including K-12, college, and adult/continuing education. It maintains liaisons to the Chicago Public Schools and the American Association of Chemistry Teachers (AACT). The Division engages the general public in chemistry-related educational activities, participates in ACS activities at the annual Illinois State Fair, and publicizes all events and news-related content. The division oversees the annual Project SEED program for the Section as well as the Project SEED scholarships. The Division also assists public officials and other community bodies concerning chemistry-related matters. The Education and Outreach Division includes the Education, Outreach, Project SEED, and Public Affairs Committees.

    The EDUCATION COMMITTEE provides chemistry-related educational programs and information to learners of all ages and actively engages with educators at the pre-K-12 and college levels. Subcommittees include:

    • AACT Liaison
    • College Education Subcommittee
    • Continuing Education Subcommittee
    • Chicago School Board Liaison
    • K - 12 Education Subcommittee

     

    The PUBLIC AFFAIRS COMMITTEE ensures that section members and public officials and bodies are informed of matters where the knowledge and practice of chemistry is of substantial public importance. These matters can include government issues, environmental issues and the social responsibility of chemists. The Public Affairs Committee gives the Public Affairs Award biennially.

    The OUTREACH COMMITTEE engages the general public, educators and children in chemistry-related educational activities and participates in many different types of events around the greater Chicago area.   Subcommittees include:

    • Community Activities Subcommittee
    • Illinois State Fair Subcommittee

     

    PROJECT SEED COMMITTEE identifies interested low-income and/or minority high school junior and senior students who are interested in participating in a paid summer research experience with  a college or university faculty member.  It supports financial and logistical concerns for the student/ faculty relationships and communicating  relevant program information to the national ACS organization.  The committee is also responsible for distributing Project SEED awards to support the internships. 

    The Measure of A Molecule

    Kids, is there an easy way to compare the sizes of gas molecules?  Yes there is, and all you need are two regular balloons and some helium.  Have one of the balloons inflated with helium (you can go to a store and ask them to inflate a regular balloon for you).  Then inflate the second balloon with air.  Try to make the second balloon as identical to the first balloon as possible in size and shape.  Leave the balloons next to each other for a couple of days.  Observe and compare the size of each balloon as time goes by.  What happens? 

    Please note:  All chemicals and experiments can entail an element of risk, and no experiments should be performed without proper adult supervision.

    Even though a balloon may look like it has a solid surface, it really has very small holes in it.  These pores, as small as they may be, are big enough to allow gas molecules out.  In this experiment, we had two balloons with two different types of gases in them: air and helium.  Air is mostly oxygen and nitrogen.  Since the helium balloon deflated faster (it should have, anyway!), the helium gas molecules must have been smaller than either the nitrogen or the oxygen molecules.  Therefore, we can use a balloon to compare the sizes of gas molecules.

    Nitrogen and oxygen are in a group of gases that are called “diatomic”.  This means that their molecules exist only in pairs.  You don’t find, for example, oxygen by itself as O in nature.  Instead, you find O2. Helium, however, is not part of this group and exists purely as He. In terms of atomic size, O and He are fairly similar. But in terms of molecular size, O2 and He are different enough to measure just by using the balloon test. Since nitrogen and oxygen are bigger than helium, they have less chance of escaping through pores such as those found in the balloons. Therefore, the balloon inflated with air should deflate more slowly than the one with helium.

    Other diatomic gases include hydrogen (H2), fluorine (F2), nitrogen (N2), and chlorine (Cl2). In addition, bromine (Br2), a liquid, and iodine (I2), a solid, also appear in pairs. Try to devise your own acronym to help memorize these special elements based on their chemical symbols (like HOFBrINCl?).


    Note:  don’t use Mylar balloons; that’s a different ChemShorts article (April 1996 “LeakBusters”); also check June 2003 for a twist on helium vs. air balloons).

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    Kathleen Carrado Gregar, PhD, Argonne National Labs 
    [email protected]
    May 2005

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    Reference (found through the National Science Foundation website):  http://people.bxscience.edu/~chinyu/2690/exper/exp2.htm