From: L M <btquant**At_Symbol_Here**OPTONLINE.NET>
Subject: Re: [DCHAS-L] Liquid methane experiment in class
Date: Fri, 10 Apr 2015 08:23:16 -0400
Reply-To: DCHAS-L <DCHAS-L**At_Symbol_Here**MED.CORNELL.EDU>
This issue is more complex than just the risk
associated with this "liquid methane" demonstration.
Teachers are often motivated to do demonstrations
that will hopefully motivate students to work more on their chemistry
studies. Every teacher of every subject has the same challenge, to
motivate their students, especially given the competition from a myriad of
electronic media and games. In some cases, this "wow" factor application may
even be encouraged and/or rewarded by supervisors.
I saw a similar application demonstrated decades
ago at a meeting of the Chemistry Teachers Club of New York. Methane from the
tap was liquefied by being run into a test tube that was immersed in liquid
nitrogen. At that time there was considerable debate about the wisdom of
building LNG (liquefied natural gas) terminals in NY City and on Long Island.
Within that context the demonstration may have been a valuable lesson. What
would happen if there was a tank rupture leading to the transporting of gas
through the sewers? The procedure shown in this video seems far from
Since the methanol incident in January 2014, at the
Beacon School, I have been re-motivated to do presentations to teachers
with the theme of "how to avoid doing potentially career ending demonstrations"
while still balancing the desire to impress and motivate students. One
must also stand up against the forces that would prohibit all real, hands
on, chemistry experience in favor of computer simulations.
Although there is required safety training, my
experience has been that most presentations are perfunctory, just to meet the
nominal requirements. Teachers and other staff may be bored by the repetition of
the same story year after year. Long before the OSHA and PESH
requirements, NY City schools had a Science Safety Manual for grades K-12. Every
science teacher was required to certify in writing that they had read the
manual, each year. As you can imagine, everyone signed, but who knows how
many read it or re-read it each year.
With the assistance of materials from Jim Kaufman
at LSI, I have done 2 similar presentations in NY City during this school year.
While not very well attended, the reaction of the teachers has been enhanced
awareness and appreciation of the risks they may be taking. My emphasis is
to encourage finding "safer" alternatives. Is the demonstration really
necessary to teach a particular principle? Are there less risky materials to
use? One of the attendees pointed out that if you cannot find a safe way, you
can use YouTube, etc.
As newsletter editor for the Chemistry Teachers
Club of New York, I have been including articles and excerpts of the accident
and incident reports from this group, especially those involving schools. Next
Friday is our annual "demo derby" meeting, at NYU. All attendees and
demonstrators are informed that appropriate safety procedures must be observed.
Some of these demonstrations are done just for their entertainment value, but
when done in a classroom, they should be tied directly to the
Chemistry Teachers Club of New York
UFT Science Committee, Co-chair
Brooklyn Technical High School
----- Original Message -----
Sent: Thursday, April 09, 2015 12:38
Subject: Re: [DCHAS-L] Liquid methane
experiment in class
And this Daily Mail article allegedly identifies the school and
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