Sciencemadness Discussion Board

Expensive experiments for the amateur experimenter

The WiZard is In - 16-5-2011 at 05:01

Charles Romley Alder Wright
The Threshold of Science
Charles Griffin and Company
London 1891
[Has been reprinted - or DL from Google.com/books.]

CHAPTER VII.
Solution Of Gases In Solid Solvents And Separation Of Gases From
Solid Solutions, No Chemical Action Taking Place.

Expt. 81. Absorption of Hydrogen by Palladium.—One of the simplest ways of causing palladium to absorb hydrogen is to decompose acidulated water by means of a voltaic current, whereby two gases are evolved—hydrogen at one pole or electrode and oxygen at the other. If the terminals of the wires leading from the voltaic battery are made to be strips of thin palladium foil, the strip attached as the " negative " electrode, at which the hydrogen is disengaged, will absorb most of the liberated gas, and in so doing will increase somewhat in dimensions, the metal swelling as it absorbs the gas, much as water does when it absorbs ammonia (Expt. 74). When a strip of palladium foil, or a thin palladium wire, is fully charged with hydrogen in this way, a slight elevation of temperature suffices to expel a little of the occluded gas; in consequence the charged metal can be used as a candle or torch; when the end is held for a moment to a light the heat expels some of the hydrogen, which takes fire and burns ; the heat thus produced causes morehydrogen to be liberated, so that the flame keeps burning for some time, the metal being clothed with a very pale flame, almost invisible in daylight, somewhat as though it had been dipped in strong alcohol, and then fired before the spirit evaporated.

Expt. 82. Palladium Eels.—A curious effect may be produced by taking advantage of the fact that palladium expands when it absorbs hydrogen. "Varnish one side of each of two long narrow strips of palladium foil with shellac or other impervious varnish, and then connect them with the wires of a sufficiently powerful voltaic battery, and immerse them in water to which a few drops of sulphuric acid have been added; the water will then be decomposed by the current, and the hydrogen evolved at the negative pole absorbed by the palladium strip. As only one side of the strip is in contact with the water, the other being protected by the varnish, only one side becomes charged with hydrogen, and in consequence this side only swells; so that the strip by and by becomes curved and bent round, ultimately twisting up into a sort of coil or spiral on account of the expansion of the charged side relatively to the other one. When one strip is thus pretty fully charged, reverse the direction of the current; hydrogen will now be evolved on the surface of the second strip, which will soon begin to curl up like the first one; but simultaneously oxygen will be evolved on the surface of the first strip, and this will act chemically on the hydrogen already absorbed, removing it, and consequently discharging the gas dissolved in the metal, and causing the latter to shrink again. The effect of this is that the one strip coils up and the other uncoils, as though they were alive. When this action has gone on a while, it may be renewed in a different way by again reversing the current; the second strip, that formerly coiled up by virtue of its swelling through absorption of hydrogen, now uncoils in consequence of the shrinking through removal of hydrogen; and vice versa with the other strip.

I haven't made an extensive search for the price of Palladium,
this is from top of the list @ Google.

http://www.surepure.com/products.php?ID=1&subCat=7&s...


----------
[Presumable — Gold coins were a 'hole lot less expensive in
1891 or Amateur Experimenters were a lot richer!]

Expt. 69. To penetrate Gold by Mercury.—Wet a small gold coin with mercury (by well rubbing), and allow it to stand some time; it will become so brittle that it may easily be broken in half; and if the fractured surfaces are examined, it will be seen that the mercury has crept inwards, and become distributed throughout the entire mass, the action much resembling the passage of water into a mass of blotting paper, excepting that with the blotting paper the pores are relatively large, and will admit any fluid capable of wetting the paper; whereas the gold, if porous at all to mercury in the same sense that unglazed pottery is to water, is only porous to that fluid, and will not allow other fluids to pass into the interior of a solid lump, even though these fluids are freely capable of adhering to, or wetting the exterior surfaces of the lump of gold.
Silver is similarly penetrated by mercury, though not quite so readily as gold.

Caution.—In certain experiments, where fluid mercury is used (e.g., collecting gases, as in Expt. 280), it is well to take off one's watch and chain, rings, &c; otherwise these may be seriously damaged by the action of little drops and splashes of mercury accidentally coming in contact with them. Amen

------------
Kids Get Swift Lesson, In Power of Mercury

Not even a month back in school, and already, were fascinated
with the silver speck bouncing the class topics seemed to hold
little promise. around his hand as if it were alive.

"Density," Mr. Science told his eighth graders.

"Today's class is on density."

Mr. Science held up a tiny little bottle of mercury, which is very
dense indeed, but not the den¬sest example of ordinary matter.
Gold is. And be-cause Mr. Science teaches eighth graders in a
poor neighborhood, there is plenty of gold around, all of it hanging
from the necks of his students or ringed around their fingers. No
school can afford to use gold as an example of density. In fact, at
this school, there is no money for test tubes.

"Density is a valuable tool used in identifying rocks and the
minerals in them," Mr. Science said.

He teaches earth science, Mr. Science does, so rocks and minerals
are never far from his heart.

"The densest common material available is gold, which has a
density of 19— that's 19 times the density of water. Mercury has
a density of 13, or 13 times the density of water. This is a bottle of
mercury."

Mr. Science handed the teeny little bottle of mercury to one of the
stu-dents, who gasped. It weighed about a pound because mercury
is so dense.

"Oooooh," said some students.

"Ahhhhh," said the others.

Mr. Science was pleased. The lesson plan had called for the
students to be amazed by the weight of such a tiny little bottle of
mercury. "Wait for students to oooooh and ahhhhh," said the
lesson plan.

Another note in the lesson plan said don't take the mercury out of
the bottle today, save it for another day, for the lesson on
amalgams. These amalgams are combinations of mercury with a
solid metal, when the mercury gets sopped up the way water is
soaked into a dry sponge. Say, mer¬cury and gold. But that was
for another day. The class period was caming to an end.

"Mr. Science?" said one of the boys in the class. "Mr. Science,
could I hold some of the mercury.

Now about the only thing most people remember from earth
science class is that mercury is fun to play with, since it rolls
around in little balls and slides across the tables, frequently
falling off and shattering into even more little balls. Quicksilver is
one of the nicknames for mercury. It acts like water but stays in
the shape of a bead, not spreading on a sheet of paper or the poor.

Mr. Science gave the student a tiny drop of mercury. The others
crowded in for a look and were fascinated with the silver speck
bouncing around in his hand as if it were alive.

"I want some too, ple-e-e-ase Mr. Science?" said another.

How could he say no? How could he deny their thirst for
knowledge? As Mr. Science gave the kids the little tiny pieces of
mercury, the bell rang. Instead of stampeding out the door, the
young scholars played with the mercury. They held it in cupped
hands, pushed it along tables, rolled it along their books.

Then, as the next class was starting to arrive, the students
gathered the bits of mercury and put them back in the bottle for
Mr. Science's next lecture on density. Two classes came and went,
and these, too, wanted to play with the mercury. In all, Mr.
Science was very pleased. Everyone seemed to be grasping the
concept.

Two hours after the first clam had ended, one of the girls from that
group returned to his classroom.

"Mr. Science? Look what the mercury did to my ring!"

The ring was in three pieces. Mr. Science was shocked, but
recovered quickly.

"Obviously, it was a very weak ring," said Mr. Science.

She was impressed but not comforted and perhaps she thought a
wicked thought or two about the boy who had given her such a
cheap ring that it fell apart when one little drop of mercury
touched it.

A moment later, another girl arrived with gold crumbs.

"Mr. Science, look at my ring, what the mercury did!"

Within a minute, his first period students were rolling in the door of
the class fast as little ball's of mercury on the loose. They were
holding. rings, necklaces, jewelry of all twists and turns. A few had
fallen apart. In the rest, the mercury had plated what once had
been a gold surface. Mr. Science gulped and fretted that soon
parents would be knocking down his door in anger.

In the halls, though, the students were dazzled. Soon all the eighth
graders in the school were clamoring for mercury.

No way, said Mr. Science, thinking about the upcoming lesson on
amalgams. The way water clings to a sponge. How the liquid
mercury joins, surprisingly, with a solid metal. The way gold
jewelry clings to the bodies of poor kids.


New York Newsday 21ix90



Morgan - 16-5-2011 at 14:55

That seems like a good book, especially for so long ago.
Here's a vague account on palladium electrodes although sadly a Darwin award winner.
It would be interesting to use some high surface area sintered palladium electrode to see just how much hydrogen you could load it up with and then see how it reacts with the air. I have a gram of palladium black powder but no foil to toy with. I would have liked to try the flaming palladium foil demonstration.
http://www.deseretnews.com/article/202425/CHEMICALS-SUSPECTE...

"At room temperature and atmospheric pressure, palladium can adsorb up to 900 times its own volume of hydrogen in a reversible process.[41]"
http://en.wikipedia.org/wiki/Palladium

The WiZard is In - 16-5-2011 at 16:50

Quote: Originally posted by Morgan  
That seems like a good book, especially for so long ago.


What I would like to know before laying out a bunch of $$$$'s
is what thickness foil works/works best. Followed by - how did
they discover this effect?!

a_bab - 17-5-2011 at 00:25

Chemistry professor in the front of the students:
"Now, what do you think will happen if I put my gold ring in concentrated nitric acid?"
"Nothing", replies John.
"How did you know that?"
"If it would be attacked by the acid, you would have not put it in acid in the first place"

AndersHoveland - 17-5-2011 at 21:47

Expensive experiments for the amateur experimenter?

Can we include expected medical receipts for treatment of likely inflicted injury?
In that case, let me suggest the reaction of diazomethane with chlorine dioxide.

(diazomethane, in addition to being a very deadly gas, is so unstable that it can spontaneously explode in contact with scratches present the glass vessel containing it; for that reason it is recommended that the glass used to handle it be flame polished prior to use)

Presumably, if there was excess hydrazine, the diazomethane would further react to form methyl hydrazine, since it is an alkylating regent. (also might be a good route if one wants to prepare N-methyl hydroxylamine

In terms of expensive metals, I would be interested in PtF5, or even Au2F10, which is supposedly a stronger fluoride ion abductor than even SbF5. I would do much more experiments with AuCl3 is gold was not so expensive. Soon we might not be working with silver nitrate anymore if the price of silver continues to increase as it has been doing...
(but I think that is a bubble waiting to burst)

[Edited on 18-5-2011 by AndersHoveland]

Morgan - 25-5-2011 at 06:00

I have a 4 ounce bottle of 0.5% palladium on carbon rods, they look like broken fat pencil lead pieces. If I mist/spray them with methanol nothing seems to happen, no heat evolved. But if you wait a few minutes and get down eye level with the petri dish they are in, you can see heat waves but no flame. They are slow to react with methanol but once they get going they get really hot.
So I was wondering if I could somehow load them up with hydrogen gas and then expose them to air to create a similar effect as the palladium foil electrode burning in air?
I also have a 4 ounce jar of 0.5% palladium on alumina pellets, I could stack them like little fuel rods. They also exhibit a slow evolution of heat with methanol but again once they react with methanol for a minute or so, they also become quite hot.
Maybe I could fashion a crude electrode out of them or expose them to hydrogen gas in order to "load them up".

AJKOER - 28-5-2011 at 09:40

If we are including medical receipts, loss of hardware including your body parts, then I would nominate the historical favorite Nitrogen Trichloride, NCl3.

I would spare someone and not mention preparation techniques as this light sensitive, shock sensitive and organic material sensitive compounds repeatedly surprises.

I believe the single biggest mistake is that someone thinks I will just make a 'little', and well, it will be OK.

From what my friend once told me, a drop of NCl3 is more powerful than a corresponding drop of nitroglycerin, but with a much worst attitude, hence the carnage!

[Edited on 28-5-2011 by AJKOER]

[Edited on 28-5-2011 by AJKOER]

The WiZard is In - 28-5-2011 at 10:43

Quote: Originally posted by AJKOER  
If we are including medical receipts, loss of hardware including your body parts, then I would nominate the historical favorite Nitrogen Trichloride, NCl3.

I would spare someone and not mention preparation techniques as this light sensitive, shock sensitive and organic material sensitive compounds repeatedly surprises.

I believe the single biggest mistake is that someone thinks I will just make a 'little', and well, it will be OK.

From what my friend once told me, a drop of NCl3 is more powerful than a corresponding drop of nitroglycerin, but with a much worst attitude, hence the carnage!


Nitrogen chloride is considered to be one of the most dangerous bodies to
handle, owing to the facility with which it explodes, by shock, friction, or contact
with various bodies.

M. Berthelot 1892


Nitrogen trichloride was discovered by my good friend, physician and professor
of physics at the École Polytechnique Pierre Louis Dulong. I first meet him at
Berthollet's home at Arcueil just south of Paris, where Berthollet had settled
following his return from Napoleon's abortive Egyptian campaign. All the greats
meet their; Berthollet's neighbour Laplace, Arago, Bérand, Biot, Amédée
Berthollet (Claude's son), Chaptal, Collet-Desostils, de Candolle, Gay-Lussac,
Humboldt, Malus, Poisson and Thernard. Napoleon showed his approval of our
meetings by allowing the use of the title "Société d'Arcueil" for our gatherings.

Pierre D. first published notice of his discovery in Schweigger's J. Chem. Pharm.
8, 32 (1812). Shortly there after he lost and eye and three fingers when a sample
exploded in his laboratory!! Indeed our mutual friend Humphry Davy was also
severely injured although happily not maimed by an unexpected explosion of a
small quantity of Pierre's "une nouvelle substance detonnante". [Later Gay-
Lussac and Thernard suffered from inhaling hydrogen fluoride fumes.]

"The preparation and handling of this compound requires the greatest care.
Every vessel employed must be washed by alkali-lye in order to free it from
grease; even grease from the fingers may cause an explosion. The substance
[yellow oily liquid] is very liable to spontaneous explosion, and thick gloves, and a
face shield are indispensable." It is also possible to cause it to explode by
exposure to strong sun light or the light of a magnesium flame!

Small amounts of nitrogen trichloride can be created during the production of
chlorine:

3.4 Other Nitrogen Trichloride Incidents

1949, February 4 and 6. Croton Lake Gate House, New York City Water Supply.

The official report is as follows: "A ton container (No. 3058) which had been
shipped from Syracuse on multi-unit car SPX 8501, was reported leaking by the
foreman of Croton Lake Gate House. The container, which had been placed in
vertical storage, was placed under vacuum hood, and the water injector was
apparently carrying off the fumes satisfactorily.

Solvay arranged to get our Chlorine Emergency Kit from South Kearny, New
Jersey. Mr. Weil arrived on Thursday morning, February 5th, and proceeded to
investigate. The hood was raised and after removing the valve hat, it was found
the leak was through the threads at the base of the valve. It was apparent that
erosion and progressed too far to permit stopping the leak by tightening the
valve. Accordingly the capping device from the emergency kit was applied and
the leak stopped.

A temporary line was connected from the container to the chlorine gas manifold
in the adjacent chlorinator room. An experimental Wallace & Tiernan chlorinator
was operating from the chlorine manifold at a rate of 2040 pounds (approximately
1/3 capacity), equivalent to a feed of 170 lb. of chlorine in two hours. Five other
vertical ton containers on individual scales were also connected to the manifold,
but all were shut off when No. 3058 was opened to the line.

A water shower (38o) was applied with sufficient flow to prevent ice forming on
the outside of the container. However, this did not provide sufficient flow of gas,
and so container in No. 3 position was opened sufficiently to maintain 8 to 10
pounds pressure at the chlorinator.

Various readings were recorded at two hour intervals to establish the amount of
chlorine removed from No. 3058. It was planned to continue use of the chlorine
by this method until the container was empty.

On February 6 the container, apparently empty, was turned off at 9:00 P.M. and
exploded at 9:40 with a report heard across the lake.

Ton container No. 3058 had ruptured the side wall nearly all around the
circumference near the chime opposite the valve end. A roughly oval section
about 18" x 11" blew out nearly completely. The container fell over and rested
with the base only about two feet from the center of the original position.

The upper part of a 12-inch diameter cast iron wheel was broken from the ton
container carrying rig which was standing nearby, and the two broken pieces
were found respectively about 24 ft. and 29 ft. away. A step ladder was crushed,
and the floor and adjacent brick wall were splashed with a reddish-brown
substance apparently iron chloride. Two upright pegs (about 8" length of 3/4"
pipe) from the small skid on which the container had been standing were torn off
and found about 18 ft. away in one direction and about 20 ft. in the opposite
direction. The water shower rig was lying nearby apparently undamaged.

The emergency device No. 3 had jarred loose but remained inside the chime.
The chlorine line was still attached, with the valve on the container wide open but
with the valve at the manifold closed and no chlorine leaking into the container
from that source.