Date: Wed Feb 28 14:07:56 2007 Back to Contents

Author: William Beaty

Subject: Re: Demos that use mercury

Post:


Looks like scitoys.com has sold out of Galinstan, but they still offer
Gallium on their sales page. And I misremembered the melting temperature:
it's 30C, not 45C.

Here's a possible trick: if for some reaon you need to make a hole in a
conventional mirror's aluminum film, you can dissolve it using gallium!
(IIRC, circuit board FeCl etchant works well too.)


Galinstan demos
http://www.scitoys.com/scitoys/scitoys/thermo/liquid_metal/liquid_metal.html

Galinstan
http://en.wikipedia.org/wiki/Galinstan

Small bottle of Gallium: $30
https://www.scitoyscatalog.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=SC&Category_Code=H





On Wed, 28 Feb 2007, Santos Ramirez wrote:

> I also recall another demo that used mercury.
> It was a small copper disk, that would rotate on a horizontal
> axis. Part of bottom of the disk would rest in a trough of
> mercury. Details are a little sketchy, think it was
> an eddy current demo. Do you have that one too?
>
> (I changed the subject line since this is getting away
> from the "lab guy" topic)
>
> Santos
>
>
> > I have one of those on shelf somewhere, It also had the cup of Hg, and
> > a center post. Put current from a hanging wire and the wire would
> > rotate, I believe this was Ampere's or Oersted's experiment.
> >
> > Don't have the guts to fire it up. The Hg has been stored and the cups
> > etc amalgamated to get an residual Hg.
> >
> > dave
> >
> > David A Kardelis, Ph.D.
> > College of Eastern Utah 435-613-5125
> > 451 E 400 N 435-613-5996 (Fax)
> > Price, UT 84526
> >
> > -----Original Message-----
> > From: tap-l-owner@lists.ncsu.edu [mailto:tap-l-owner@lists.ncsu.edu] On
> > Behalf Of Santos Ramirez
> > Sent: Wednesday, February 28, 2007 8:42 AM
> > To: tap-l@lists.ncsu.edu
> > Subject: Re: [tap-l] LabGuy Rot Suggestions
> >
> > Talk about mercury vapor....
> >
> > Brings to mind
> > a demo that consisted of a mounted vertical spring that had one
> > end dipped in a mercury cup. A current was run through
> > the spring and the mercury, causing the spring to contract.
> > The end of the spring would lift out of the mercury, breaking
> > the circuit. The spring would then drop, re-starting the process.
> > You could see the vapor.
> >
> > Wonder if this is in a museum somewhere?
> >
> > Santos
> >
> >
> >
> >> "I'm doing asbestos I can!"
> >>
> >>
> >> On Feb 27, 2007, at 12:12 PM, Sam Sampere wrote:
> >>
> >>> More for labguy rot...
> >>>
> >>> 'dems only mercury vapors. Don't need no stinkin' respirator.
> >>>
> >>> A little asbestos dust won't hurt ya.
> >>>
> >>> Get shocked by those open contacts once and you'll learn never to
> >>> touch
> >>> them again.
> >>>
> >>> Cough cough cough.
> >>>
> >>> Sam
> >>>
> >>> -----Original Message-----
> >>> From: tap-l-owner@lists.ncsu.edu [mailto:tap-l-
> >>> owner@lists.ncsu.edu] On
> >>> Behalf Of Santos Ramirez
> >>> Sent: Tuesday, February 27, 2007 12:25 PM
> >>> To: tap-l@lists.ncsu.edu
> >>> Subject: Re: [tap-l] LabGuy Rot Suggestions
> >>>
> >>> Bill,
> >>>
> >>> I think this list better reflects a "lab guy"'s requirements
> >>> than someone that needs to quit. :) Might fit on a T-shirt. SR
> >>>
> >>>
> >>> Could call it:
> >>>
> >>>
> >>> YOU ARE A "LAB GUY" IF ...
> >>>
> >>>> A: Knows the location of everything in the Demo Room-- or at least
> >>>> where it /was/ before someone borrowed it.
> >>>>
> >>>> B: Has every published edition of Halliday and Resnick.
> >>>>
> >>>> C: Personally knew Sutton.
> >>>>
> >>>> D: Knows the meaning of the the acronym "PIRA".
> >>>>
> >>>> E: Can set up any demonstration in any lecture hall on campus in 10
> >>>> minutes flat. And is frequently asked to do so at the last
> > minute...
> >>>>
> >>>> E: Has at least 195 of the "PIRA 200" demonstrations in their
> >>>> department collection.
> >>>>
> >>>> F: Can explain even the most basic demonstrations to the most
> >>> advanced
> >>>> professors.
> >>>>
> >>>> G. Can recall the last dozen bars visited with Ziggy during AAPT
> >>>> meetings. 10? 6? 1??
> >>>>
> >>>> Cheers.
> >>>>
> >>>> bill
> >>>>
> >>>>
> >>>>
> >>>
> >>>
> >>>
> >>
> >>
> >
> >
> >
> >
>
>

(((((((((((((((((( ( ( ( ( (O) ) ) ) ) )))))))))))))))))))
William J. Beaty SCIENCE HOBBYIST website
billb at amasci com http://amasci.com
EE/programmer/sci-exhibits amateur science, hobby projects, sci fair
Seattle, WA 425-222-5066 unusual phenomena, tesla coils, weird sci

From tap-l-owner@lists.ncsu.edu Wed Feb 28 14:07:56 2007

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