Demonstrations

Homemade hiking stoves that use alcohol as fuel have become quite popular in the past 5 or so years here in the U.S. Basically, they are a cheap copy (made from a soda can)of the age old brass Trangia alcohol stove made by the Svea folks in Sweden.

Adding a wee bit of boric acid to the fuel, will yield a green flame.

Of the three alcohol fuels available- methanol, ethanol, and isopropanol This green flame stuff only works with the methanol. Methanol burns with a clean, almost colorless flame. Ethanol has a more incandescent candle-like flame and isopropyl burns with a sooty yellow flame.

Linky ad nauseam....

http://www.ultralight-hiking.com/stoves-trangia.html

http://wings.interfree.it/

http://art.simon.tripod.com/Stoves/

http://zenstoves.net/Stoves.htm


Drygas. In colder climes, water condenses on the cold gasoline of your car's gas tank. Being denser than the gasoline, it sinks to the bottom of the tank where it can gets slurped up by the fuel pump and stalls or hesitates your car engine. Alcohol drygas, being miscible in both gasoline and water helps make a more homogenous suspension of water in gasoline to help prevent stalling. Its actually more of a cloudy/murky suspension, but it keeps the water off the bottom of the fuel tank.


Be sure to use the methanol drygas (methyl alcohol), the isopropyl ones burn like crap in a stove and doesn't pick up the color. Don't drink it, as methanol gets oxidized into formaldehyde in the human body. Your eye's will be embalmed first, then your liver and peripheral nerves.
There is no ethanol drygas since it would be too pricy. All that fermenting and stuff...


The secret ingredient. Boric acid. You sprinkle this stuff around and the bugs gobble it up as they groom themselves. Pretty non-toxic to people, but bad news to roaches apparently.


Label close up. Boric acid is NOT to be CONFUSED with BORAX (sodium tetraborate)a laundry additive which comes is a big, green 5lb box or for sale next to the MSG in chinatown!
Boric acid is a weak antiseptic usually used in eyedrops, but pharmacies hardly carry it anymore. Nowadays I can only find it in Walgreens or Homedepot in the bug killing section.



Just add a pinch or two of boric acid to each pint of methanol, mix, and it will burn a delightful green color. Any more than a wee bit simply won't dissolve and will be sediment in your fuel. Its an ancient chemistry trick, and of all the funky flame color demonstrations, its the only one you can produce in liquid form. Others require introducing solids to a colorless flame or a pyrotechnic type device/reaction.


My half-assed stove is leaking at the seams. Oh well.

Experimenting The Sharper Image for poor folk. For people with windows, I put together quick paper weights made from xylene and water. Pretty funky, but until now, I never made one for myself. At home, it didn't turn out as well as the ones made in lab, but its not a gift either.




Goof Off stain remover. I got it at a Walmart in the paint section. Home depot probably would have been a better bet for pure xylene, but I doubt it would have come in such a convienent size.


Goof Off label. From the smell, its mostly xylene (dimethylbenzene). Actually less toxic but not as pleasant as Toluene (methylbenzene) of "old School" model airplane cement and TNT fame. Its great for dissolving greasy or waxy things. In fact, a candle will dissolve in the stuff. Slowly, but it still dissolves. Xylene will dissolve many, but not all plastics too, especially the polystyrene of model tanks and styrofoam.


I got this good looking bottle at lab. A good old fashioned "Boston round" bottle. It was to be my paperweight.


I poured in half xylene, (goof-off) half water, and the xylene immediately started turning cloudy. Bummer, I should have got the purer stuff at Homedepot. The cloudyness is probably from some alcohol mixing ever so little water with the xylene. A quick shake to see if things stay separate, and my beautiful boston round looks like crap. I gave up.


A week went by and the xylene cleared up. I don't know why. So I tried to color the water (bottom layer) to get my funky paperweight/window ornament done, but had no water soluble coloring. Bummer. I did have some grungy copper sulfate laying around and tossed that in.


Looking pretty sorry. Worst of all, there are little pockets of water clinging for dear life all over the glass.



After some thought, I moved to plastic. Plain old soda glass (I guess)is just plain too "sticky" for the water in my desk toy. I realized that the ones I made for friends in lab were of pyrex lab glass which for whatever reason, doesn't give me as many stuck water droplets.
Come to think of it, all of the commercially made ones feature plastic housings.


Variation on a theme. Sometimes I'd make an "upside down" paper weight thing using Oil Red O, a dye which only dissolves in fatty, greasy oily substances. It gives you a pretty red in the xylene layer, and leaves the water alone. Of course, I didn't have any of that so I stuck a black permanent type marker in the xylene and swished it around.


Not too shabby.



I should try other colors of "permanent" marker.

See story Life imitating art?





Liquid Lightning Drain remover. Good stuff for when Drano just doesn't cut it.


Ah ha! The secret ingredient. 12 buffers? thats just dumb marketing



When lay people think of "acid" they often think of bubbling, boiling, fuming reactions with flesh and metal.
Few acids act in such a cartoonish way, or at least, don't act FAST ENOUGH to produce fuming liquified whatever. Concentrated Sulfuric does not disappoint and may in fact be the very thing from which our cartoon notion of acid came.
Its serious stuff to be respected. So becareful with the Oil of Vitriol.


Seriously strong stuff. It even dissolves paper,(which alkaline Drano et.hydroxides do not) due to its crazy reactive affinity for water. Protect your eyes, wear gloves and pour from arms length. But man, will it unclog the drain. It also tends to discolor the plumbing too, another con to its use vs. Drano et. hydroxides.


T=0 Having just added sugar to the brown sulfuric acid. Ordinarily it would be a clear, slightly viscous liquid, but hey, this is drain cleaner, not lab grade sulfuric. Liquid Lighting is sort of crude, as it still smells of sulfur, which the pure acid does not.


T=30 seconds. All of the sugar has turned black and you can see the sugar granules have lost their cuboid shape as they dissolve. The brownish translucent color of the acid can be seen toward the edges of the bottlecap. The sugar is turning black as water molecules are ripped away by the water hungry acid, leaving the carbon skeleton.


T=2 minutes
The hydrolysis of the sugar (a carbohydrate) continues. Everything is dark black syrup. The sugar is dissolved as it is broken down into its components carbon, hydrogen and oxygen (carbo, hydr,& ate), more specifically in this case, carbon and water (H2O) as steam.
The molecular formula for table sugar (sucrose) is C12H22O11. Indeed Carbon and H2O (water)


T=2minutes 30 seconds
Uh OH. What is this? The darkly carmelized sugar is mostly carbon now with released water molecules emerging with enough energy to exist as steam. Of course steam is a gas and bubbles though the carbon/carmel sugar sludge.


T=3 minutes
Bigger still


T=3 minutes 30 seconds
It fell over


T=3 minutes 45 seconds

A little side spurt of boiling water with no sugar sludge to fill. Its not much of a "snake" but I was trying not to wake the neighbors with odd odors. Maybe I'll try outside on a larger scale.


close up of resulting carbon nugget


Kind of like pumice but much more brittle.

An oldie but a goodie. Ammonium chloride smoke. Lately, when the computer folk despair, I bust out some lab stuff for them to play with on their desk. Why not make it so everybody can play. I have this quiet dream of teaching the world about science, but hundreds of pupils later, I doubt I have made much of a dent.
Its simple enough. Hydrochloric acid is simply Hydrogen chloride dissolved in water. Ammonium Hydroxide is ammonia gas dissolved in water. Dissolved gases don't tend to stay dissolved so well. So they diffuse.
The hydrogen chloride (HCL) diffuses out of solution and reacts with the free ammonia (NH3) forming ammonium chloride (NH3Cl-the smoke) and water (H20-invisible). Classic acid/base reaction resulting in a salt and water.

Laboratory Hydrochloric acid. Note the crusty salt stuff around the neck of the bottle. Despite being screwed shut, a wee bit escapes and reacts with the air, forming crust.



Laboratory Ammonia 30% concentration

Bringing the ammonia bottle to the mouth of the crusty HCL bottle=smoke

Of course you can do this at home!

Household ammonia from the supermarket (about 3% concentration, but thats plenty)


Hydrochloric acid from HomeDepot or the hardware store known as Muriatic acid.
Its for cleaning up after laying brick or for removing stains in the swimming pool or bathroom.


Closeup of the label. Don't get it in the eyes and keep it away from nylon. Nylon will dissolve. It won't work too fast on skin, just rinse off.

Can't stand hardware stores? That's OK you can get similar stuff at Walmart for 94cents. "The Works" toilet cleaner.


You see, its the same stuff.


Dump a little of ammonia and a little acid on separate paper towels, and you get the smoke. Acid on the left (white cap, ammonia(base) on the right (green cap)

More Walmart smoke.




Walgreens has hydrochloric acid toilet cleaner too, but its weaker.




Walgreens acid makes anemic smoke.


Whats this good for? Desktop smokescreens of course.

A penny snapped in half (with pliers) after immersing in liquid nitrogen



I think in 1983 it became too expensive to make copper pennies completely out of copper. So entered the copper-clad zinc penny. They ping a little different when dropped, and science teachers have been dissolving pennies' insides as a demonstration for a couple decades now. Its amazing just how little copper is used. So I cut loose with the camera while waiting on stuff baking in the oven. I even tried to measure the thickness of the resulting "paper" penny with iffy success. The zinc dissolves in hydrochloric acid but the copper does not. Entry locked to prevent the internet from ratting me out Homeland Security :-) I think all that stuff of squishing pennies on the train tracks (or dissolving them) being a crime is bunk. Teachers have been messing up pennies for years. Just google it.



Ye Old Muriatic acid from the mini smoke screen entry


The toilet cleaner works too, as long as it has the hydrogen chloride.


Scrape a few edges on the curb an toss it in the acid. Bubbles are hydrogen.

About 90 minutes later...

Not a whole lot of copper here.




Not only are they filled with zinc, its impure zinc. Look at that insoluble crud.

4 layers= 5 one-thousandths of an inch (5/1000in.)

8 layers= 8 one-thousandths of an inch (8/1000in.) Huh?

12 layers= 14 one-thousandths of an inch (14/1000in.) Just doesn't add up.
Quite a bit of variation, then again these caliper things probably aren't the best thing for this kind of measurement. Plus, I'm just screwing around waiting for the pie to cook.

Elemental iodine is intriguing stuff. There are plenty of cool things to be learned and done with it, but for now...


Iodine is a halogen, the family of elements containing Bromine Fluorine, Chlorine and the rare Astatine which is only made via nuclear decay and which decays rapidly itself. Most commonly encountered as Tincture of Iodine (a brownish alcohol solution of iodine) or as Betadine/povidone-iodine ( a reddish brown water solution of iodine and some stuff called PVP-polyvinylpovidone which acts as a sort of slow release agent. Both used as antiseptics, the tincture stings because of the alcohol.

Just like chlorine, it is an oxidizer by trade, and it is this very activity which kills bacteria and inactivates viruses. Crystalline iodine is hard to come by, but its a very interesting and strange chemical element.



Polar Pure, an iodine based water disinfectant used for hiking. Purchased at a local REI store.


Light interacts with iodine to give less reactive "iodide", hence the brown bottle.



Pretty clever. A stubby pipe is stuck in the bottle to trap the iodine and prevent it from being poured out. You don't want to swallow crystalline iodine. You'll get the tummy ache of doom.



Some fierce shaking gives up some of the contents. Little millet sized pellets of crystalline iodine


Shiny eh? A "lustrous solid" is the age old description. Iodine is wierd in that it sublimates like dry ice. It turns directly to gas.
Its also much more soluble in alcohol, oil, and fat than it is in water.



To stain oils, a ziplock bag with some paper I folded.

the setup

Zip up the iodine in the bag and go do something usefull for a while (>20minutes)



post development. Oh ho, something looks different.

post development from back





Iodine stains the oils from the skin. Oil (sebum) made by peculiar epithelial cells which commit suicide and leap into the ducts of the sebaceous glands.


Reference:
http://www.redwop.com/technotes.asp?ID=79

PDF of the same
http://www.redwop.com/download/iodine.pdf

More iodine later...

I remember reading one of Richard Feynmann's books (Surely you're joking...)and marveling over the freedom he had as a kid to futz around with science stuff. He had a little place he'd go to fix neighbors radios, deep fry potatoes to eat, and performed little chemistry "magic shows". In retrospect, letting a kid deep fry potatoes in hot oil over an open flame now sounds like a disaster waiting to happen. Part of the patter/effects for his chemical show would be to place iodine in a small watch glass and have it heated to form purple clouds of smoke. I'm almost certain Oliver Sacks described performing the same thing in Uncle Tungsten

But, sadly kids today will never see such things.

I attempt to resurrect this parlor trick with a twist.
Its an old, well documented reaction which is unusually neat because it is initiated with a drop of water. Contrary to the cartoon notion of labs, few things outside of acid-base pH reactions producing anything with beautiful, striking color.

The intro to iodine is in this entry where a common (though pricey) source of iodine is described and how its vapors can be used to develop latent fingerprints from porous materials such as paper, by staining the lipids left behind.


Polar pure granules=Iodine


zinc powder from the inside of a D sized alkaline battery. Alkaline batteries are awfully....alkaline- care must be taken to avoid caustic burns. Its not as scary as it sounds but--More details on this elsewhere/later. Zinc has its own set of tricks.


a simple mixture. Washed and dried zinc and the polar pure iodine.


add a drop or two of water, and you get a beautiful cloud of purple iodine vapor.

The zinc metal gives up electrons to react with the oxidizer, iodine, forming zinc iodide. Enough heat is released to vaporize the remaining iodine rapidly to form the cloud. The reaction is actually a bit more complicated as the zinc iodide can react with more iodine (in water) to produce another, reddish, water soluble product (triiodide ion), but in short, the the zinc iodide creation gives the heat to vaporize the iodine.

The iodine vapor actually smells quite a bit like bleach (and a bit irritating like bleach), which makes sense as chlorine is a halogen as well. Except that iodine stains things rather than bleaching them, though both chlorine and iodine are oxidizing agents.


more typical iodine crystals from my collection of old science stuff. Almost metallic looking, though absolutely non-metal.

repeat reaction with larger proportion of reactants

couple more drops of water

a couple more drops still




Another repeat.

No discussion of iodine would be complete without mention of nitrogen triiodide. The last entry on iodine hinted at triiodide ions and their reddish appearance. Simply put, nitrogen triiodide is an extremely impressive and sensitive contact explosive. Mix 2 ingredients, let it dry and you get a dark sludge which will explode with an amazing ear piercing snap at nothing more than a faint breeze. A beautiful purple cloud of iodine vapor results, similar to that described in the last entry.

Its a common college demonstration and quite a crowd pleaser. Its terribly impractical but certainly worth the experience of making just once in a lifetime.(or twice, to get things just right.)

Danger? Not really. A little bit goes a long way, and its simply just not feasible to make big enough quantities to do much in the way of nefarious activities. Its just too sensitive, and iodine is too expensive. The sensitivity makes it sound more dangerous than it really is, but its that very sensitivity that defuses the hope for dangerous shananagans.

Bazzam Shakhishiri published instructions in his first volume of chemical demonstrations. It calls for 30% ammonium hydroxide which just plain isn't available outside of the lab. Here I make the stuff with 10% "Janitors' Ammonia" and it works just fine, but the nitrogen triiodide it produces appears different than what I'm used to.

His movie of the reaction is here

another little movie is here.



old friend iodine




strong ammonia

Ammonium hydroxide is simple ammonia gas (NH3) dissolved it water. Ammonia gas is incredibley soluble in water. Confusion comes about since ammonium hydroxide is usually refered to as "ammonia" by us common folk who buy it at the grocery store. Commonly found in 3% concentration with a bit of soap added. Its great for cleaning up greasy things, and unlike other strongly alkaline things, it evaporates leaving a clean surface.

Warning to those who have never dealt with "ammonia"-- it has an incredible irritating, eye watering odor. (the odor is actually ammonia gas diffusing out of solution) Its very chacteristic and quite "sneaky" Wafting the vapors towards you nose is necessary for a smell. Stick your nose close to the bottle and you may smell nothing at first. A deeper inhale will leave you with an olfactory punch to the head.


warnings. read the label
Get it in your eyes and you'll be screaming for momma. Spilling it on skin (as with all ROOM TEMPERATURE ie.not hot- alkaline solutions) is no biggy as long as you rinse it off right away. Strongly alkaline solutions feel quite slippery, like soap (in fact they convert some of the lipid in your skin cells to soap) and require a bit more rinsing than other things.




THE INSTRUCTIONS:

1 Put some iodine is a plastic cup.

2. Get yourself a place with good ventilation and then cover the iodine with the ammonia solution. Put a little extra for good measure.

3. Mix briefly and come back in 10 minutes

4. Decant liquid and dispose down the sink. Pour remaining sludge onto something absorbant to absorb remainder or waste liquid. (don't bother trying to filter, its too much trouble)

5. Move the sludge to whereever you are going to wait and wait for the sludge to dry. (and detonate)



finished product

When using the lab grade 30% ammonium hydroxide, I immediately get a dark sludge which can then be divided up for demonstrations. When using the DIY janitors' ammonium hydroxide, I get more of a dark sediment instead of a goopy sludge. No fear its the same thing. The sediment takes a few minutes to form, so giving the reaction a good 10 minutes or more isn't a bad idea.


decanted

Probably enough there for 6-7 q-tips of fun. You don't need much.

on Q-tip.

I usually roll q-tips (usually the longer medical applicator sticks) with the triiodide product and stick them in styrofoam to dry. That way everybody gets to try. On a q-tip, it takes a good 2 hours to dry, which is good if you are setting up for a class or demonstration.

For the impatient, you can dry the triiodide product with acetone or alcohol, but be wary that you'll immediately have product on hand and nowhere to put it without it detonating while both your hands are full while washing the product. Acetone dries very fast.



The old gag of spreading the triiodide about and letting people step on it is amusing and probably a better way to demonstrate nitrogen triiodide to those who can't wait for the q-tips to dry. Globs of various sizes will dry at various times over the course of an hour and you'll be constantly setting off small, sharp, harmless explosions while you walk around.

While trying to convince people to stick around for their personal q-tip to dry, triiodide that I've inevitably spilled dries over the course of a discussion and explodes underfoot, building suspense for the bigger q-tip dose.

You can leave larger quantities to dry out, but I feel that its a waste. A q-tip full gives give a hearty explosion with all the ear ringing you can handle. Plus, making several aliquots makes the fun last longer.

Magic rocks



I became acquainted with sodium silicate in the third grade. It was a component in my little Christmas chemistry set, which came with the maddening manual describing all manner of wonderful chemistry experiments for which my kit hadn't the ingredients. It did have sodium silicate solution, but is was dried out, leaving a glassy gem to be frustrated with. I was also told lies (by way of the manual) that sodium silicate solution, so called "water glass" can be had with a quick visit to the hardware store.

It really is a watery glass. When dry, its clear, waterproof, and brittle like glass. Once upon a time (when my manual was written) it was a half-assed solution to broken glass problems.
I think the invention of super glue and later epoxy sealed its fate when it came to fixing broken stuff in the china closet. Its still used to waterproof matches. Although the waterproof matches you buy at REI for hiking are so skinny that the match often breaks while you try to ignite them through their glassy coating. And when mixed with a bit of clay it becomes known as "muffler mender" which you can buy in the auto parts store. You slather some of the goop onto the rusty holes of your exhaust system and hope it effects some repairs. It does work if you slather alongside some fiberglass cloth cut to wrap around the exhaust, but thats something I figured out on my own. At most "muffler mender" comes with a tiny bit of metal window screen to act as a patch. And you can still find "water glass" in the auto parts shop as a radiator leak filler. You pour it into your antifreeze and, of course it will eventually leak out and harden over time, "plugging" your coolant leaks. Sheesh.

Last, but not least, sodium silicate solution ("water glass")is a key ingredient to "magic rocks" an age old science toy which is becoming much harder to find these days, as is most all quality science stuff.
Contents of the magic rock kit. I found this in the bargain bin at a Walgreens. I guess the Killer Whale was supposed to be the selling point.

Silica desiccant packet. I would find these in the bottoms of shoes or baseball mitts, most with "DO NOT EAT" emblazoned on them Added to all sorts of things to prevent mildew growth I suppose. At some point (while perusing the merck index I think)I figured out silica was sodium silicate. Desiccant packets are kind of expensive. Too expensive to buy or collect en masse just to screw around with.
Also, I didn't know how to dissolve silica gel. Its insoluble in water. It certainly absorbs a fair amount of water, but it doesn't dissolve. I did know that sodium silicate solutions were strongly alkaline, and I let that guide my judgement. Plus, from my old job, if I had a a hard to dissolve item, I'd attack it with strong acid or base, provided that such treatment didn't destroy the item of interest. Silica, being practically glass, I figured it would dissolve yet not react.

And then the world changed.

Sodium silicate rears its head again, but in more economical amounts. Plus it doesn't hurt that I have a cat.

Deodorant? I bet, for a variety of reasons, said deodorant is water soluble. I'm too lazy to wash this stuff, but luckily I have a leaky tub faucet. I put a bunch of litter in a bowl and placed it under the leaky faucet until I felt the urge to continue with this little project. After moving in and out of the tub for a few days, I gathered some enthusiasm, check with a sniff, and sure enough, no deodorant to smell.

Time to turn it into solution. To make a strong and pure alkaline solution I dissolve a couple spoonfuls of sodium hydroxide (lye) in a cupful of water.
Red devil lye is the shit. Other drain opens are unsuitable. Drano et al. has bleach in it. Powdered drano has bleach AND little bits of aluminum which generate heat (and hydrogen gas) while reacting with the hydroxide to melt hair and fat, plus it gives some effervescent look to the drain opening process. And hey, it dissolves hair in the drain pretty damn well.

Be sure to read the label and be careful, its potent stuff. It'll take a minute or two to get through skin, but its serious bad news for mucous membranes like the eyes or mouth.

Mix in a few spoons of litter and let it sit for awhile.

All told, I managed to dissolve about 10 spoonfuls of silica litter to go along with the 2 spoonfulls of lye. Perhaps, I could have dissolved a lot more silica had I used more lye, but I felt this was plenty, plus I'm just screwing around. Nothing too scientific. Little remants of blue remain. Apparently just plastic coated silica added to make things look cool.

After dissolving, I put a coffee filter into another dixie cup which had a whole poked in the bottom, and dropped the whole thing into one of those ridiculous big cups you get at McDonalds when you order a large drink. Some kind of Boston Redsox advert. The filter cup stuck in the top and left space below to catch filtrate. I filtered the chunks out of my silica litter solution.



From my reading at chymist.com, I needed some sort of transition metal salt. A metallic salt made from one of those mundane metals from the "middle part" of the periodic table.

Left over from when I tutored a homeschooler last year.

rainbow flame label. Ah ha, copper sulfate.

Contained within, little nuggets of Copper Sulfate and some granular crap to burn.

Rocks at the bottom of a cut off soda bottle Filled with my newly made sodium silicate solution which had been DILUTED 1 part to 2 parts water in a crude attempt to follow the "magic rocks" instructions.

Within a couple minutes, little tendrils form.

I go to bed (at 5am ugh.) and awake to my "magic rocks" in the morning (10am)





experiment from the night before

Maybe I should try the actually magic rocks to see how much better they work, or not.
Anyways, homemade magic rocks (of one color) and sodium silicate solution by the bucket for kids to play chemistry, make waterproof matches or poor into the car's radiator to close leaks and muck thing up in general.

Funny money on Christmas

When I have kids I will haunt them with funny coins.




Years ago (1990) a wise old man (28yo) dared to teach me a thing or two about physics. I never did pick up on physics (my mind doesn't get along with math) but I learned an enormous amount of science, especially how to think, from this wise old man full of sage advice on investigating the universe.

Once he told me of a childhood "trick" of turning quarters into "pennies". Coins into "gold" He heated coins on the stove and dunked them in ammonia. They came out all coppery like a penny. Sometimes the coins turned out all iridescent with funky rainbow colors.

The cashiers at stores would give him funny looks.

I tried this with an old hotplate bought at a yardsale and ammonia bought at a drugstore (amongst the laundry/cleaning stuff). I kept getting grungy grey coins and a few iridescent ones. On a whim I tried Windex (with ammonia) and got the copper colored coins.

Goofing around, I found that the two colors of coins could be produced depending on how long they were heated prior to quenching in the windex. Later, when caught without my hotplate, I discovered that a gas stove gave me better, prettier, more consistent "pennies"



Regular propane torch flame.
Gas stoves are becoming rarer, in my experience. The little bachelor cooking hotplates available today don't get red hot like my old yardsale one. An electric stove works well too, but I find the focused torch flame heat more agreeable than cranking up the stove to "full blast". Plus I'd keep dropping coins between the coils of the electric stove. Annoying




Heating the quarter for a little bit leads to the first change. A funky bluish change of color across the coin. Quenching the coin at this point gives you the iridescent colored coins. (no bigger mystery here)


Shortly after the bluish change is complete, it turns a deep grey.


Once red-hot, drop it in Windex to quench. A soda bottle cap full works nicely.




You get a funny quarter.

Whats going on here is actually a bit of a mystery to me. Beyond my mentor, I've never come across any reference to this effect or "trick" anywhere. Not even in the Bazzam Shakhishiri books.
Coinage contains copper. The coin looks like a raw pennie. Aqueous solution of ammonia do dissolve copper, albeit slowly to yield a deeply blue solution of copper ions.
There is one demonstration where red hot copper in placed into a jar of acetone fumes. It gives heat and a lovely salmon colored copper, but its a different animal of chemistry altogether I think.

Does Windex have dissolved copper in it? No. Just water, ammonia and 2-butoxyethanol (according to the MSDS) Plus I have got this to work in "plain old ammonia" as well. Some brands work better than others, and I suspect this is due to contamination with soaps and the like, these agents adding the suds to "sudsy ammonia"
I suspect the hot coin, copper and all, dissolves a wee bit in the windex (the copper most preferentially) and then immediately the copper condenses on the coin before reacting with the ammonia? Hmmm. Well, I'm just guessing.

Honestly, I don't understand it, but it gives pretty results.


Reducing flame. The oxygen poor inner part of the flame. The busting of bonds within propane give the flame its blueish hue. A shiny copper like patina to the coin appears while under the reducing parts of the flame. The rest of the coin simply glows from incandescence.
Hmmm. Interesting


Parts of the coin held under the reducing parts of the flame come out darker, greyer.

Hmmm. Interesting. Meaning? Dunno.


Close up of a coppery quarter

"ripened" quarter.
Been sitting around for a few months. Looks much more like a well used penny.


More "ripened" coins with various shades of oxidation. Both black and blueish

composite.
2 iridescent coins, a coppery one, plus an untreated one straight from my pocket


close up of the transition colors. Most likely the metals reacting in the air.

One of my favorites. The pickle lamp is nothing new. When I first heard about it back in 1991? it was a sort of obscure demonstration. But now it is known most everywhere. Just google "pickle lamp" or "pickle light". I haven't much to add. You plug in a pickle and it glows (and stinks). The glow comes from sodium ions being excited by the electricity-electrons jumping to orbitals of higher energy, then returning after emitting the extra energy as a photon of light- orange light.
Sodium D line emission.
Many elements have a distinctive emission/absorption spectra, but they are harder to demonstrate with household voltage!

Read up : http://research.hp.com/techreports/Compaq-DEC/WRL-TN-13.pdf

A fantastic "tongue in cheek" report on pickle lamps.



Firstly, your typical modern-day GFCI outlet. Designed to spare you electrocution should you drop your toaster in the tub while bathing.


Ages ago (10-15 years?) both slots were "hot". Nowadays only the small slot is wired to current.
(IF and only IF it was installed properly)
Here I am testing the outlet. You see? The big slot carries no current! I'm actually not that brave, I tested it with a meter first...



The setup. An extension cord where I snipped the end off, split the wire, stripped it and wrapped it around two forks. Added some plastic wrap and a lot of electrical tape to secure the wire and keep bare metal exposed to a minimum


Plug it in T=30 seconds and steamy.


Lights out

carbon spark :more gold colored than orange. Emitting light via incandescence, NOT atomic emission.


Vaporizing its way through the pickle


"blanching" the pickle to get more light

red hot copper "nightlight"


Just a neat trick. Copper as a catalyst.




Quite a few metals can act as a catalyst for various reactions (usually oxidation) but this little demo I learned from Ben Salinger's "Chemistry in the Marketplace" - an exceptional book which is only in print in Australia. From here its a short jump to understanding how automobile catalytic converters or those funky flameless propane heaters work- Both are platinum based.


Not much needed A tall narrow vessel is best to act as a chimney to direct vapors. Also for safety's sake if the acetone happens to ignite, the flame will be snuffed out almost immediately in a narrow mouthed vessel. Just about any glass jar will do, where as using a saucer or plate may may leave you confronting a fast hot flare up.


Nail polish remover label, few volatile components.The acetone is what is needed. All those compound names that end with -ate are oily acids with high boiling points. They won't be evaporating very readily.


stripping wire A sharp blade scraping almost parallel to the wire

a simple copper coil

setup
just a dribble of acetone based nail polish remover in the bottom of the jar


heating the wire with a cigarette lighter.
The incandescent outer part of the flame which is oxygen rich, oxidized the metal to dark copper oxide. The inner, cooler oxygen deficient part of the flame is a reducing environment. The carbon atoms from the butane which normally combine with oxygen in the outer part of the flame and glow with incandescence, now have oxides on the metal to rip oxygen from. This reducing flame leaves a clean pure copper surface. The can see the difference between inner and outer parts of the flame.


heat the wire until it glows then plunge into the acetone atmosphere. The hot copper acts as a catalyst oxidizing the acetone (a ketone) to an aldehyde. Supposedly the product is acetyldehyde (the stuff of hangovers/drunken flushing) but it sure doesn't smell like acetyldehyde. Acetyldehyde smells very grape-like. The heat released continues to heat the copper. Nifty

lights out




lowering the coil almost to the surface of the liquid acetone yields more heat, melting the wire and sometimes igniting the acetone vapors.

more melting


No magic here, but at first blush its odd to see something glowing red hot with no obvious heat source. Traditionally the demonstration is done with a copper penny, but its harder to get the penny red hot nor does it glow as brilliantly.- a surface area issue





reduction oxidation interface. The area between hot and cold where the range of temperatures led to varied oxidation (and colors)

aftermath

test