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Vomaturge
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Potassium permanganate and glycerin, water boiling at room temperature and reduced pressure, hydrogen balloons filled using aluminum and sodium
hydroxide.
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Morgan
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Here's an apropos jam jar jet demonstration for the chemistry crowd or stress testing the borosilicate glass.
Erlenmeyer Flask Jam Jar Jet Snorkeler
https://www.youtube.com/watch?v=mDrdUy-LWHY
[Edited on 28-11-2019 by Morgan]
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Morgan
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Musical Flames and other excerpts
From the physicist John Tyndall's book "Sound" in the 1800's.
A long tube in the verticle ...
Fig. 114. Fig. 114.A still more striking effect is obtained with this larger tube, a b, Fig. 114, 15 feet long and 4 inches wide, which was made for a
totally different purpose. It is supported by a steady stand, s s′, and into it is lifted the tall burner, shown enlarged at B. You hear the
incipient flutter: you now hear the more powerful sound. As the flame is lifted higher the action becomes more violent, until finally a storm of music
issues from the tube. And now all has suddenly ceased; the reaction of its own pulses upon the flame has beaten it into extinction. I relight the
flame and make it very small. When raised within the tube, the flame again sings, but it is one of the harmonics of the tube that you now hear. On
turning the gas fully on, the note ceases—all is silent for a moment; but the storm is brewing, and soon it bursts forth, as at first in a kind of
hurricane of sound. By lowering the flame the fundamental note is abolished, and now you hear the first harmonic of the tube. Making the flame still
smaller, the first harmonic disappears, and the second is heard. Your ears being disciplined to the apprehension of these sounds, I turn the gas once
more fully on. Mingling with the deepest note you notice the harmonics, as if struggling to be heard amid the general uproar of the flame. With a
large Bunsen’s rose burner, the sound of this tube becomes powerful enough to shake the floor and seats, and the large audience that occupies the
seats of this room, while the extinction of the flame, by the reaction of the Fig. 115. Fig. 115.sonorous pulses, announces itself by an explosion
almost as loud as a pistol-shot. It must occur to you that a chimney is a tube of this kind upon a large scale, and that the roar of a flame in a
chimney is simply a rough attempt at music.
The action reminds one of the story of the Swiss muleteers, who are said to tie up their bells at certain places lest the tinkle should bring an
avalanche down. The snow must be very delicately poised before this could occur. It probably never did occur, but our flame illustrates the principle.
We bring it to the verge of falling, and the sonorous pulses precipitate what was already imminent. This is the simple philosophy of all these
sensitive flames.
A flame of astonishing sensitiveness now burns before you. It issues from the single orifice of a steatite burner, and reaches a height of 24 inches.
The slightest tap on a distant anvil reduces its height to 7 inches. When a bunch of keys is shaken the flame is violently agitated, and emits a loud
roar. The dropping of a sixpence into a hand already containing coin, at a distance of 20 yards, knocks the flame down. It is not possible to walk
across the floor without agitating the flame. The creaking of boots sets it in violent commotion. The crumpling, or tearing of paper, or the rustle of
a silk dress, does the same. It is startled by the patter of a rain-drop. I hold a watch near the flame: nobody hears its ticks; but you all see their
effect upon the flame. At every tick it falls and roars. The winding up of the watch also produces tumult. The twitter of a distant sparrow shakes the
flame; the note of a cricket would do the same. A chirrup from a distance of 30 yards causes it to fall and roar.
At a distance of 30 yards, for example, the chirrup of a house-sparrow would be competent to throw the flame into commotion.
Curved roofs and ceilings and bellying sails act as mirrors upon sound. In our old laboratory, for example, the singing of a kettle seemed, in certain
positions, to come, not from the fire on which it was placed, but from the ceiling. Inconvenient secrets have been thus revealed, an instance of which
has been cited by Sir John Herschel.16 In one of the cathedrals in Sicily the confessional was so placed that the whispers of the penitents were
reflected by the curved roof, and brought to a focus at a distant part of the edifice. The focus was discovered by accident, and for some time the
person who discovered it took pleasure in hearing, and in bringing his friends to hear, utterances intended for the priest alone. One day, it is said,
his own wife occupied the penitential stool, and both he and his friends were thus made acquainted with secrets which were the reverse of amusing to
one of the party.
The celebrated French philosopher, Biot, observed the transmission of sound through the empty water-pipes of Paris, and found that he could hold a
conversation in a low voice through an iron tube 3,120 feet in length. The lowest possible whisper, indeed, could be heard at this distance, while the
firing of a pistol into one end of the tube quenched a lighted candle at the other.
[Edited on 2-2-2021 by Morgan]
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Morgan
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Quote: Originally posted by Morgan ![](images/xpblue/lastpost.gif) | Yesterday I was toying with a pale yellow mushroom that forms a sack with a goodly amount of spores inside, the kind that billow a lot of smokey
spores when popped. The mushroom wasn't some perfectly round kind you sometimes see but an odd very light weight, pale yellow and brown, elongated
bumpy membrane somewhat egg-shaped and it didn't seem to have an pronounced attachment point where it rooted to the ground. So the thought was to see
how the spores might burn if held next to a lit Bic lighter.
Surprisingly, when the partially split sac of spores was compressed near a flame the fireball the burning spores made was quite perky, reminiscent of
lycopodium powder. So if you had a large amount of these which were collected for their spores, perhaps they'd be a comparable/alternative "dragon's
breath" source, slightly quirky or road less traveled.
I wonder if you had someone standing by with a lit propane torch if this puffball spore cloud would burst into flames?
https://www.youtube.com/watch?v=5TeFsg9e-ks
Update
Researching Astraeus hygrometricus recently perhaps it's spores would work as well as lycopodium for some effects if you could gather enough of them.
I bought a couple of 3 ounce bottles of lycopodium spores a few years ago, which is fairly bulky like powdered charcoal but not all that inexpensive.
https://youtu.be/rXGy2KjefDw
[Edited on 24-2-2021 by Morgan] |
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Piroz
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Burning various compounds in stream of oxygen is nice experiment, I tried this few years ago with some chemicals: sulfur, titanum, aluminium,
magnesium, iron, charcoal, wood and sugar:
https://youtu.be/lYtUHB1LtfY
Other amazing experiment that I tried is spectacular autoignition of finely powdered zinc with ammonium nitrate with some ammonium chloride. After add
a drop of water it "explodes" with greenish- blue flame:
https://youtu.be/uYjyH1ZQXdI
[Edited on 24-2-2021 by Piroz]
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Morgan
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Here's a clever variation on a theme. Sometimes you see a sleeve over the tube to modulate the pitch like a trombone, but this was amusing.
The world first blowless flute - I play a melody on my thermoacoustic engine
https://youtu.be/Qqk36IZqIgY
Another more basic variant
Singing Test Tubes
https://youtu.be/iN2P6KU9bEg
I was wondering if a battery driven tiny piezo speaker/tone generator placed inside a tube with holes at the end could be played as musical instrument
in a band for novelty. It would be funny to see a flute-like instrument but without the need to have it near your mouth or constricted by having a
flame tied to it, walking around while you played it.
[Edited on 9-4-2021 by Morgan]
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ChemichaelRXN
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Oil and vinegar
No just kidding...
I liked the video by ChemicalForce where he mixed carbon disulfide and Potassium superoxide. It explodes like it was a high explosive almost. (I dont
deal with explosives...laws etc. I just watch youtube)
You are the same perception looking out, from the same elements around the universe.
You are everything to be anything to begin with.
Https://you-are.space
Https://syntharise.com
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Morgan
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I saw this repurposed device that might be handy for some demonstrations. There're some for less than $20.00 on ebay.
Mini Handheld Tesla Coil(Oudin Coil
https://youtu.be/x0QmomYHt_I
Say for things like this or whatever creative use you might think of.
Volta's Pistole,Volta's Pistol
https://youtu.be/WZerYRGU33c
Methanol Cannon
https://youtu.be/Wn5wr9ZAq3s
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Morgan
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Quote: Originally posted by Morgan ![](images/xpblue/lastpost.gif) | Yesterday I was toying with a pale yellow mushroom that forms a sack with a goodly amount of spores inside, the kind that billow a lot of smokey
spores when popped. The mushroom wasn't some perfectly round kind you sometimes see but an odd very light weight, pale yellow and brown, elongated
bumpy membrane somewhat egg-shaped and it didn't seem to have an pronounced attachment point where it rooted to the ground. So the thought was to see
how the spores might burn if held next to a lit Bic lighter.
Surprisingly, when the partially split sac of spores was compressed near a flame the fireball the burning spores made was quite perky, reminiscent of
lycopodium powder. So if you had a large amount of these which were collected for their spores, perhaps they'd be a comparable/alternative "dragon's
breath" source, slightly quirky or road less traveled.
I wonder if you had someone standing by with a lit propane torch if this puffball spore cloud would burst into flames?
https://www.youtube.com/watch?v=5TeFsg9e-ks
After looking over some photos I think it's possible that the mushroom I found was an earthstar as there were a few dozen banana peel looking things
in my lawn that came after some rains. If you look at the 3rd photo that's sort of what my flammable spore ball looked like but more of a potato shape
without the perfect round shape with a pointy top.
http://www.realmonstrosities.com/2013/06/earthstar.html
Or it could have been something like this poisonous earthball.
http://www.wildutah.us/html/plants_scenery/h_mushroom_earthb...
[Edited on 31-1-2017 by Morgan] |
Having thought puffball spores might make a good substitute for a lycopodium dragon"s breath demo it seems if you worked with the spores a lot or were
more allergic than most people for some reason, maybe there could be a slight risk to your health. In the above, there's a guy who runs over a giant
puffball with his mower creating a big cloud of spores.
"In one particularly unfortunate case, a group of eight apparently sober teenagers decided it would be a good idea to inhale the spores squeezed from
some puffballs they had acquired. After a couple of days, they started to cough, had trouble breathing, ran a fever, and felt generally crappy. Things
got so bad that five of the teens were hospitalized, two of them needing to be intubated to help them breathe. Their inflamed lungs were treated with
corticosteroids and they all eventually recovered from their illness."
"Lycoperdonosis has also been seen in people who snorted puffball spores as a folk remedy for a nosebleed. Both puffballs and earthstars have killed
or seriously injured dogs who disturbed them and inhaled their spores as they ran about or dug holes."
http://www.rosincerate.com/2016/03/how-bacteria-and-fungi-ca...
It seems even lycopodium can be hazardous in some cases.
https://www.sciencedirect.com/topics/pharmacology-toxicology...
[Edited on 18-10-2021 by Morgan]
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Plunkett
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This demonstration is more material science than chemistry, but you take a length of music wire (high carbon steel) and stretch it between two ring
stands. Then you pass an electric current through the wire causing it to heat up. As the wire heats up it starts to sag from thermal expansion, but
when the wire hits the austenite transition temperature the wire lifts slightly as the body-centered cubic ferrite in the steel is converted to the
more densely packed face-centered cubic austenite causing the wire to contract. The wire then starts to sag again as the temperature is increased.
The effect is more pronounced in reverse when the wire contracts as it cools, then sags at the phase transition temperature, and contracts as it cools
further.
https://youtu.be/W6Pa4n4Abyw
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karolus28
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maybe not a demonstration but If you mix some glycerol with potassium chlorate and ignite, it burns for a bit and when hot enough it goes
うじゅうぅぅ〜〜ん! Big flame upwards - I think it's pretty cool
Hi, please read about exif data.
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Morgan
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Maybe not much chemistry, but some pressure, volume, and temperature gas laws and heat transfer going on. Anyway, just a very simple external
combustion toy using a couple of test tubes in a tube. I was initially using the bottom tube to take up volume but found it moved if upturned.
https://youtu.be/EosXGSEvkuU
https://youtu.be/trCiuU69YcE
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SWIM
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If those puffball snorters are the ones I'm thinking about, they thought the puffballs were hallucinogenic.
There were some erroneous reports of puffballs that produced auditory hallucinations in some old popular books on hallucinogens from the 60s or 70s.
I think Schultes may have been involved in these reports but am unsure and don't want to blame a guy who generally did great work. I think they were
the species marginata.
The reports weren't about snorting spores, but puffballs are often found when over-ripe, and at that stage they're not like tasty mushrooms but like
little leathery sacks of spores.
Edit: I see Dave Aurora believes these reports, but I'm pretty sure they've been discredited. (But If you want to learn US mushrooms Aurora's
mushrooms demystified is a great book.)
[Edited on 18-4-2022 by SWIM]
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Morgan
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This is more of a physics demo category, but the way a small sealed volume of heated air can shuttle about was curious to observe. It's just some
steel wool and a silicone breast milk pump diaphragm in a clear quartz crucible and then sleeved to a silicone milk bottle cap held to a Euler's disk
with a small flat magnet. Maybe of interest.
Stirling Jumper Sounding Like a Euler's Disk When Stopping
https://youtu.be/KfbRd5LtIxc
PS I wonder if there's a way to tell how many Hz it's cycling at just using the sound?
[Edited on 15-2-2023 by Morgan]
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Jeeves225
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A visually pleasing demonstration I really like is the separation of dyes using column chromatography.
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Morgan
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Here's a pretty simple engine that doesn't take much time to make.
Easy Balloon Three Piece Stirling Hot Air Jumper
https://youtu.be/B547cKwERzI
And a souped-up version. At the 1:14 mark it appears stretched and motionless for a couple of seconds.
https://youtu.be/ciHfynKzFE0
[Edited on 19-2-2023 by Morgan]
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Dr.Bob
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I like the chemistry demos using black powder, fuel, oxidants, and various metals salts organixed into sphers or cylinders, being ignited while in a
tight fitting tube. Great way to demonstrate atomic emission spectroscopy, along with redox chemistry and the production of auditory energy from
chemicals.
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Morgan
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Trevelyan's Wieger,Wackler,Rocker,Instrument
https://www.youtube.com/watch?v=U23iwbVX-Dk
Trevelyan Rocker
https://www.youtube.com/watch?v=D51nazEkutE
The article is fairly extensive, the various metals, properties and variations that were tried and the accounts of this discovery by Trevelyan and a
few others were interesting as they worked to understand the effect.
"In the year 1829 Mr. Arthur Trevelyan was engaged in spreading pitch with a
hot plastering iron, and observing in one instance that the iron was too hot, he laid it slantingly against a block of lead which happened to be at
hand. Shortly afterwards he heard a shrill note, resembling that produced on the chanter of the smaller Northumberland pipes, an instrument played by
his father’s gamekeeper. Not knowing the cause of the sound he thought that this person might be practising out of doors, but on going out the tone
ceased to be heard, while on his return he heard it as shrill as before. His attention was at length attracted to the hot iron, which he found to be
in a state of vibration, and thus discovered the origin of this strange music."
After seeing an above video, I gave it a try with a "design" that I arrived at using stuff that I had, trying several things until something worked.
Later I found the silver coin would rev up from a standstill, you don't have to start it moving.
Trevelyan Rocker with a Silver Dollar and Stainless Steel
https://www.youtube.com/watch?v=7wzM4iSZyWE
On the Vibrations and Tones produced by the Contact of Bodies having different Temperatures.
https://royalsocietypublishing.org/doi/pdf/10.1098/rstl.1854...
Mechanical Analysis of the Trevelyan Rocker
https://www.nature.com/articles/017242f0
"One of these lead blocks is kept in the refrigerator as the greater the difference in temperature between the block and the rocker the better it
works. Another interesting note is that the frequency of the rocker will not descend steadily, but will jump from one harmonic to another."
https://instructional-resources.physics.uiowa.edu/demos/4a30...
The Theory of the Trevelyan Rocker
https://www.tandfonline.com/doi/abs/10.1080/1478644230863631...
[Edited on 4-12-2023 by Morgan]
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knowledgevschaos
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A crystal of potassium chlorate, with a bit of sulfur, wrapped in aluminium foil and hit with a hammer can be a fun demonstration.
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Morgan
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Another variation on the Trevelyan Rocker using a piece of 1/2 inch plumbing pipe. It's just strange to watch with no apparent interaction of the
metal surfaces to cause motion on the scale visible to the eye.
Trevelyan Rocker Shower Arm
https://www.youtube.com/watch?v=pyFmHYx8Aik
[Edited on 12-12-2023 by Morgan]
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Morgan
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A coin vibrating making a fair amount of sound. It's interesting from the perspective of the properties of metals, the heat capacity, thermal
expansion, thermal conductivity, etc. Around the 1:30 second mark it makes a steady humming sound building feedback in the stainless steel tray.
Trevelyan Rocker High Pitch Resonance with a Kennedy Fifty Cent Piece
https://www.youtube.com/watch?v=7InFwKHOi38
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Morgan
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Thought is copper-magnesium alloy was mildly interesting.
Tim's Amazing Yi Bell
https://www.youtube.com/watch?v=id-u9ro50TM
"The Yi bell is used to demonstrate the relationship between temperature and oscillation damping."
https://www.a3bs.com/product-manual/U30002_EN.pdf
Copper-magnesium eutectic as phase change material for thermal storage applications: Thermophysical properties and compatibility
https://www.sciencedirect.com/science/article/abs/pii/S23521...
[Edited on 18-12-2023 by Morgan]
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Morgan
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An easy to make arrangement for this subject.
"After delivering an authoritative Friday Evening Lecture in the summer of 1853, the Royal Institution offered Tyndall its prestigious chair in
natural philosophy, which he held until 1887. Michael Faraday had been influential in this appointment, being impressed with Tyndall’s experimental
knowledge and practices, and they collaborated at the Royal Institution until Faraday’s death in 1867. 21 The topic of Tyndall’s
career-establishing Friday Evening Lecture had been an acoustic one, examining the sounds produced through heated metals, which Trevelyan, Faraday,
and Forbes had investigated during the 1830s."
https://academic.oup.com/chicago-scholarship-online/book/425...
Eye Nut Trevelyan Rocker
https://www.youtube.com/watch?v=Lgc4HgylHJU
1 2 3 Block Springs to Life as a Trevelyan Rocker
https://www.youtube.com/watch?v=eq2KY3BqCv0
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Morgan
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Perhaps this would add to the above demonstrations if a Tibetan cymbal were heated too.
Tibetan Tingsha Cymbals Versus Temperature
https://www.youtube.com/watch?v=4SOyVX4r3MA
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wg48temp9
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The Trevelyan Rocker reminds of a curious effect with steel ball bearings. If an electric current is passed between the inner race and the outer
race via the balls the races will rotate wrt each other after an initial push to get them going.
See: https://www.acorn-ind.co.uk/insight/just-for-fun-the-ball-be...
I am wg48 but not on my usual pc hence the temp handle.
Thank goodness for Fleming and the fungi.
Old codger' lives matters, wear a mask and help save them.
Be aware of demagoguery, keep your frontal lobes fully engaged.
I don't know who invented mRNA vaccines but they should get a fancy medal and I hope they made a shed load of money from it.
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