Re: [Phys-l] A Silver Spoon.

[Brian Whatcott <betwys1@sbcglobal.net>]

My older son would be cheered by the thought of asking a
 "Science Fair" question.
BC's mention of gamma activation reminded me of walking round
the McGill reactor years ago - where enthusiasts explained to me
 the idea of neutron activation, which allows determination of
 quite a few elements.

Surprising to suppose that a gas mantle would be a forbidden
object at a Science Fair. I can detect one even with a defence
survey meter.

Brian

At 12:38 PM 2/21/2006, you wrote:
> If its a science fair project (generally, if the son is under 16 (18?)
> the maximum exposure set by OSHA and Fed regulations for any
> radioactive substance is **ZERO**.
>
> Now, that's kinda funny, since the Texas Legislature meets in a
> granite building with background levels enough to explain some of
> their decisions...  Remember, GW was not the first radiation enhanced
> president to come from Texas...smile...Karl
>
> Quoting Bernard Cleyet <bernardcleyet@redshift.com>:
>
> > I remember an exercise in Frosh chem. to separate the Ag from the Cu in
> > dimes (this dates us).  All I can remember is first dissolving it in
> > acid (HCl?) and at the end throwing in salt to force completion of the
> > precipitation (common ion effect).  I'm certain Michael can tell all or
> > any old inorganic text.
> >
> > You could try irradiating it w/ gammas from a smoke detector or nearly
> > dead Mössbauer (Co-57) source, and looking at the fluorescence w/ a
> > prop. counter tube and MCA.   (even better a SS detector)
> >
> > bc
> >
> > Brian Whatcott wrote:
> >
> >> My son brought me a silver spoon and asked me to identify the material.
> >> It weighed 23.1 gm dry, and  20.5 gm submerged in water.
> >>
> >> The markings were "International Silver Co" and DAL
> >> and we supposed that this was part of an airline setting for the
> >>  first class service.  The density is on the borderline for
> >> cupronickel or Britannia metal or German silver I suppose.
> >> I know that a "metallometer" would identify the constituents,
> >> but I don't have one.
> >> I do have a Star project spectrometer, and various power supplies,
> >> so that I could sustain a spark to the spoon.
> >>
> >> I wonder if I could distinguish copper, tin, zinc, lead, nickel
> >>  or bismuth in this way? Perhaps there are easy chemical color tests?
> >>


Brian Whatcott    Altus OK    Eureka!