Favorite home experiments

[oxoiron]

Ever had trouble getting a hairspray spud gun to work? Have no fear!
First, take a fairly long pipe, and an "end". Cement the end onto the pipe-now there's only one opening.
Throw in some dry ice crystals. Pour in some water, and very quickly ram a spud down the barrel. Enjoy!

I suspect the CO₂ would not sublime quickly enough to produce a 'gun'. The potato would probably move to the end of the barrel in fits and starts until it just fell out of the end.

[explodingviolin]

Ever had trouble getting a hairspray spud gun to work? Have no fear!
First, take a fairly long pipe, and an "end". Cement the end onto the pipe-now there's only one opening.
Throw in some dry ice crystals. Pour in some water, and very quickly ram a spud down the barrel. Enjoy!

I suspect the CO₂ would not sublime quickly enough to produce a 'gun'. The potato would probably move to the end of the barrel in fits and starts until it just fell out of the end.

Both of you are technically correct. The potato doesn't have high enough a coefficient of friction to stay in the tube long enough for CO2 pressure to build. However, if you craft a firing chamber with a fast-action release valve (like those frequently used to solve similar issues in MythBusters), you could let the gas build first, then release it all at once. The only question left is at what pressure does CO2 stay in solid/liquid state (depending on temperature; there's some little annoying fact mentioned somewhere around here about how at a certain pressure you will be able to have liquid CO2 but normal 1 atm pressure is too low and it only forms a solid...etc something like that)? Because if the pressure to keep in solid/liquid state doesn't exceed, say, 30 psi (a midrange estimate, I don't suppose you seek to fire a spud gun from the ground that can deposit mashed potatoes on the antennae of the Sears Tower), you're really not going to get a spectacular ejection even with a rapid-release valve.

[cmd]

One of my favorites involves milk, food coloring, and soap.

Pour a small amount of milk into a shallow pan, a little bit more than to cover the bottom. Place four different drops of food coloring at four different locations. Dip a toothpick into your soap, and then dip it into the milk. Experiment!

[Hobgoblin]

I love the mentos and coke experiment! Here's a vid my friends and I did a few years back of changing it up a bit.

http://www.youtube.com/watch?v=bwQmz83U ... PL&index=1

.. I won't tell you which one I am, because it'd be embarrassing no matter what.

[PhaseShifter]

Okay, so to start, drink everything in your 2-liter and clean it out with water. Having done this, put a little bit of rubbing alcohol, (around half a cups worth should do it, add more if needed) shake the 2 liter.

Anything more than one or two mL is wasteful--it doesn't take much alcohol to combine with all the oxygen in 2L of air, and once the combustion process depletes the oxygen you won't be able to burn additional alcohol.

Getting away from things that go boom:

One cold night when I was in high school I poured a few drops of water on a metal rail to see how fast it would freeze. It was instantaneous as far as I could tell, but I was bored and thought I'd try something a little different...I got some rubbing alcohol and mixed it in with the water, and it didn't freeze quite as fast. I made a few more attempts at adjusting the water:alcohol ratio and eventually got a mixture that took about 10 seconds to freeze solid when I poured a few drops on the rail--and while it was freezing I could watch hexagonal ice crystals grow up to 1 cm in size.

More water and alcohol in high school--I measured exactly 10.0 mL of water in a graduated cylinder, and measured 10.0 mL of denatured ethanol in another graduated cylinder. When I mixed them, the combined volume was only 19.5 mL. (and yes, I checked and verified that both graduated cylinders were calibrated exactly the same.)

Another stupid volume trick:
Fill a cup with water until it's just about to overflow. You don't want the surface to merely be level here, you want it to actually bulging slightly due to surface tension holding the water in. Take bets on how many cotton balls you can drop in the cup before it overflows.

[Stormlock]

Now for one that most couldn't and shouldn't do at home but cool.
You can take high concentration Sulfuric acid (like 10 Molar) and some table sugar, and OUTSIDE you mix them in a beaker and mix them with a glass stirring stick then stand back and let the reaction occur, you can get some very interesting carbon "towers". Don't breathe the gases emitted from the reaction though (potentially toxic).

A teacher in training did this in my highschool science class, but she screwed it up in two ways: One, she added the sugar to the acid, instead of the other way around. No stirring required, thank you. Two (The fun part) she used DILUTED sulfuric acid. We weren't even wearing lab coats or safety glasses and were crowded around this beaker when it started boiling black burning napalm everywhere. Extremely cool (and dangerous). Car battery acid might work for this; it's about 33% dilution according to wiki. Just don't do it anywhere flammable, close to yourself, or without eye protection. Letting neighbours see might also be a bad idea.

Edit: And the flames are green!

[Bassoon]

I've recently taken to attempting to create Copper (II) Acetate by combining vinegar, some pre-1976 pennies, and heat. The reaction will occur by itself over time, but I prefer to add heat to speed it up. The resultant crystals are fun to look at. (Also, danger. I've been using boiling water for heat transfer and vinegar's boiling point appears to be slightly below that of water, thus it boils. Vinegar vapor is no fun to breathe.)

I've also looked at boiling water + baking soda. The baking soda initially appears to react to the water with bubbling and when boiled, the rest of the reaction occurs. I've added pennies to this, too, in hopes of getting Copper (II) Carbonate, despite the fact that baking soda is neither copper nor carbonate, and the pennies usually end up coated with a sort of iridescence.

They're not really experiments, per se, but they're fun nonetheless.

[FrankManic]

I prefer 98ish% isopropyl alcohol

Can't that make you go blind? I mean, even if you aren't swallowing, lots of alcohol is absorbed by one's tongue.

I believe Parafin is preferred on the grounds that it's not toxic and not very flammable as a liquid. Hence you don't get cancer and you're unlikely to blow up your mouth. Please note that kissing girls who have been blowing fire off of Kerosene is less fun than kissing girls who have not.

[FrankManic]

I always like the ones that blow off people's fingers

Experiments that go bang are the best ones, untill like sum1 dies...

That's why we have minions...

... You do have minions, don't you?

[MrKltpzyxm]

I call this one, "Egg in a bottle."
The materials you'll need are as follows
a hard boiled egg
a glass bottle (The mouth of the bottle needs to be a smaller diameter than the egg. Most are, so this shouldn't be hard to find.)
a source of fire (matches, lighter, stovetop, etc.)
a piece of paper (something combustible that can be dropped inside the bottle.)

The procedure is simple
First, place the glass bottle on a stable surface.
Second, fold or crumple the paper so that is is small enough to fit inside the bottle.
Third, light the paper on fire and place it inside the bottle.
Fourth, quickly place the egg on top of the bottle.

Results:

Spoiler:

The burning paper makes the air inside the bottle hot and so it expands.
Placing the egg over the mouth of the bottle cuts off the oxygen to the fire, extinguishing it.
The air in the bottle cools and contracts, reducing the pressure inside and sucking the egg inside. (hopefully intact because it's so much cooler that way.)

[oxoiron]

Do you know the cool way to get it out?

[SpazzyMcGee]

Double slit diffraction. All it takes is a $5 laser and a single hair and you can demonstrate the probabilistic nature of the entire universe.

[eternauta3k]

Do you know the cool way to get it out?

Double slit diffraction. All it takes is a $5 laser and a single hair and you can demonstrate the probabilistic nature of the entire universe.

That'd be a novel way to get it out

[SpazzyMcGee]

Do you know the cool way to get it out?

Double slit diffraction. All it takes is a $5 laser and a single hair and you can demonstrate the probabilistic nature of the entire universe.

That'd be a novel way to get it out

I was referring the topic of the thread... what is our favorite home experiments.

As for getting stuff out... I don't see why double slit diffraction would hurt.

[J Spade]

I think it'd be easier to put it all in the freezer for a while, then take it out and hold it upside down until the egg thaws enough to be pushed out of the bottle by the expanding air.

[oxoiron]

I used to do it by turning the bottle upside-down so the egg was sitting against the neck, then 'blowing' air up into the bottle. When I removed my lips from the bottle, the egg would come shooting out. It's the same principle as what you suggested, but using a different source of air pressure.

[MrKltpzyxm]

I didn't know how to get it out. Now I have to go try that experiment again, and the follow up!
I haven't looked through the whole thread, but has anybody posted any crystal growing experiments?

Supersaturate water with salt or sugar by boiling water and stirring in either until they stop dissolving.
pour the saturated salt/sugar water into a glass.
tie a string around a pencil or popsicle stick.
place the stick with the string on top of the glass so that the string hangs into the water.
place the glass near a window (a warm dry location in direct sunlight) where the water will evaporate.
watch the crystals grow!

[SpringLoaded12]

Inflammable means flammable? What a country!

That ALWAYS bothered me! It just doesn't make sense!

Making thermite is pretty cool, and probably illegal in several states. Of course, explosions in general are pretty cool. And illegal in several states.

These are mostly pranks as opposed to experiments, and they may have been mentioned already.

If someone is annoying you and you want them to be distastefully preoccupied, try this (you'll need access to some chemicals): slip some magnesium citrate into their drink. Magnesium citrate is a very strong laxative. Should put them in the bathroom for quite some time.

If you've got some friends around, you could do everyone's favorite science thingy: Egg Drop! Use household materials to build small contraptions that will contain an egg and prevent it from breaking after being dropped from a certain height. I think there's a thread on this forum with some ideas for designs; pretty sure it was the thread for the Egg Drop strip. Hey, try using the Non-Newtonian fluid mentioned earlier in the thread!

Liquid Nitrogen kicks ass in all categories. Get some and have fun. Try soaking a hollow rubber ball in it, and then dropping it on the ground. Should break as easily as glass.

Make a pressure-powered potato cannon out of PVC pipe. It makes a loud noise when it fires though, and a few seconds later makes a deep, loud trumpet noise. My friend did this, and we wasted 20 potatos firing the thing. SO fun.

If you don't have any nice supplies, but have some very basic materials, try pouring nail polish remover into a styrofoam cup. It's a low-strength acid, so it will slowly dissolve the cup into a puddle.

There is a chemical (I don't know what it's called, the person who told me about this refused to tell me the chemical because of its effects) that will turn urine blue, but is otherwise harmless. There is also a serious medical condition that you know you have if your urine is blue, though the chemical has nothing to do with it. This is a bit of a severe prank, if you do this to someone else you should tell them you did it after they freak out, or they will end up in the hospital spending lots of money getting tests done to see if anything is wrong. The other option is to do it to yourself so that you can have blue urine for a little while, which would be pretty funny.

Coke and Mentos! There is an easy way to convert this trick into a prank. You'll need a two-liter bottle of coke, one Mentos, a drill with a drillbit slightly wider than a piece of string, a piece of string (preferably 3 inches or longer), and scissors.
--> Use the drill to drill a hole through the Mentos. Be careful that you don't split it in half.
--> Thread the string through the hole in the Mentos.
--> Open the bottle of coke. Drink/pour out a bit of the liquid so it is not so high in the bottle; if it's too high, this may end badly for you. Hold the Mentos over the opening, with the ends of the string sticking out on either side.
--> Screw the cap back onto the bottle with the Mentos still there. It should go over the Mentos and part of the string, causing the Mentos to be held in place above the liquid.
--> Cut off the ends of the string that are sticking out from under the cap. Now the bottle is invisibly rigged.
--> While keeping the bottle straight upright, CAREFULLY place the bottle back in your fridge.
--> Now, if someone opens the bottle, the Mentos will no longer be held in place and will fall into the coke. Which means a faceful of coca-cola foam for them, and plenty of laughs for you.

it's great for parties, assuming you pull this on someone who can take a joke. But, be careful not to turn the bottle sideways. If you do, the coke will either shoot out from under the cap in all directions, or the cap will be blown off with about as much force as a cork being blown off a champagne bottle.

[oxoiron]

Liquid Nitrogen kicks ass in all categories. Get some and have fun. Try soaking a hollow rubber ball in it, and then dropping it on the ground. Should break as easily as glass.

This works great, if by 'dropping it on the ground', you mean 'hitting it with a hammer'.

If you don't have any nice supplies, but have some very basic materials, try pouring nail polish remover into a styrofoam cup. It's a low-strength acid, so it will slowly dissolve the cup into a puddle.

It doesn't work because nail polish remover is an acid, it works because it is an organic solvent. Gasoline (among many other solvents) does the same thing.

I really like the Coke/Mentos booby trap. I may try that one some time.

[Dimetrodon]

Hey, can someone explain how to do the double-slit experiment to me? I've tried it before but it doesn't seem to work. I have a laser if that helps.

[PM 2Ring]

can someone explain how to do the double-slit experiment to me?

Find youself some thick metal foil, like the kind that's used for sealing podered milk cans, etc. Cut you slits in that using a very sharp blade.

For something more robust, get a few old-fasioned razor blades & bolt them together, using some kind of thin spacer to create the required gaps.

I think it's cool that it's possible to see single slit diffraction using no other equipment apart from your fingers (unless you have very bent fingers ).

[ssbookyu123]

Get a can of butane, a fork and an emty soda bottle. Then trun the butane can upside down use the fork and press down on it with the tip of the butane can over the opening of the bottle. A wight gas should come out and go into the soda bottle. Cap it after 10 secons as fast as possable. there should be some pressure buling up so after 20 seconds twist the cap off with your thumb it should fly away pretty fast. Now you could ether leave it outside so the gas airs out. Or you could not be boring and make a flame thrower by getting a source of fire preferably a gas stove for safty resons but anything that has fire would work, immeatyly aftwer luanching the cap sqeeze the bottle relly hard right next to the fire and a gaigantic ball of flame should pop out of there you could make a ball of flame for maybe 2 or3 times more.

[eternauta3k]

immeatyly aftwer luanching the cap sqeeze the bottle relly hard right next to the fire and a gaigantic ball of flame should pop out of there you could make a ball of flame for maybe 2 or3 times more.

Bonus points if air gets inside the bottle.
Kids, don't do this. At all.

[wst]

immeatyly aftwer luanching the cap sqeeze the bottle relly hard right next to the fire and a gaigantic ball of flame should pop out of there you could make a ball of flame for maybe 2 or3 times more.

Bonus points if air gets inside the bottle.
Kids, don't do this. At all.

It should be fine, as there is a 'weak point'. However, I am not inclined to trust the instructions given by a post that has worse English than Babelfish.

[ikrase]

Freeze Mentos in ice cubes with white ice, so they look normal,.

Put in coke of people. Get them to drink it slowly.


I am trying to figure out a source of zinc to make some hydrogen.

[Cold]

You can only microwave Dove soap.

Also, it's not really an experiment, but I made a coilgun a few weeks ago.

[explodingviolin]

I am trying to figure out a source of zinc to make some hydrogen.

Er, it's on the far end, but there's a way to get the copper off a penny. A penny has a really thin layer of copper, but the inside is all pure zinc. Unfortunately, you'll need a professional chemist and a day or two to get the copper off. So...not worth it, unless you like playing with dangerous chemicals that can basically turn your skin into soap.
Or, you could disassemble a non-alkaline battery. Non-alkaline battery casings are frequently made of zinc. It's easier and comparatively practical, but again, you risk losing large swatches of your epidermis if you leave battery paste smeared on your hands. =D

After telling you all that, I'd just like to note that if you are only looking for the hydrogen, don't bother with zinc. You can whip up an electrolysis apparatus in minutes and pump out hydrogen all day. =D

You can only microwave Dove soap.

LIES, I've done it with everything EXCEPT Dove (nothing against it, just works out that I don't have Dove soap on hand to microwave). Haha, if it doesn't poof up as fast, or tends to char and smoke more than ooze like puffy marshmallows, spritz the soap with water, put it back in for a few seconds, spritz with more water, put it back in for a few seconds, repeat until you get a fluffy mass which overwhelms your microwave. And, if you're feeling creative, let the soap cool, crack it out of the inside of the microwave, then use a dinner knife to chisel it into a sculpture. Practical bathroom decorations! XD

[eternauta3k]

Or, you could disassemble a non-alkaline battery. Non-alkaline battery casings are frequently made of zinc. It's easier and comparatively practical, but again, you risk losing large swatches of your epidermis if you leave battery paste smeared on your hands. =D

Don't take my word for it, but I think the paste in carbon-zinc batteries is reasonably safe. The MnO₂ (I never remember what part of the battery it's in) catalyzes the decomposition of H₂O₂

[PM 2Ring]

Or, you could disassemble a non-alkaline battery.

Don't take my word for it, but I think the paste in carbon-zinc batteries is reasonably safe. The MnO₂ (I never remember what part of the battery it's in) catalyzes the decomposition of H₂O₂

I used to disassemble all the carbon-zinc cells I could get my hands on when I was in my teens, back in the 1970s. They were an excellent source of zinc, carbon rods & manganese dioxide. The MnO₂ absorbs hydrogen, stopping bubble formation on the electrodes, which would otherwise depolarize the cell. The paste also contains ammonium chloride, which is a bit acidic, so it's a good idea not to get too much paste on your hands, but it's not so bad if you're using old dead batteries. This NH₄Cl can be rinsed out, and the MnO₂ can be recovered by filtering & drying. The MnO₂ can be used to decompose H₂O₂ to make oxygen gas.

[mikesartin]

1. Find some alcohol-based liquid (alcohol will work fine, but you probably want to dilute it a bit).
2. Cover hand in said liquid.
3. Light hand on fire.
4. Wave hand to extinguish fire. (Optional)

As Richard Feynman mention in Surely You Jest, Mr. Feynman, don't try this with hairy hands.

[mikesartin]

I have converted a two liter bottle, two paper clips, a dc wall adapter, some water, and some baking soda into a hydrogen bubble factory.

Its really terrific to fill soap bubbles with hydrogen and then set a lighter to them. Its even louder if you can get hydrogen and oxygen in the bubble at a 2:1 ratio.

This is a great idea. Would be easy to do with a small hydrogen fuel cell.

[mikesartin]

I would like to do some home experiments related to gardening, Has anyone in the past done any on the same?

Here is a classic; I can't remember who first did it. Determine the dry mass of a seed, a growing medium (perlite and composte will do). Arrange everything so that none of the growing medium will be lost. Plant seed and grow plant. Dry everything and determine mass again. Did the mass change? Where did it come from?

[Telestriation]

This is why I want to marry these boards.

This is an amazing thing, for sure. Now to make some exploding chalk and convince someone to test the sample for calcium deposits.

[Ulc]

My personal favorite: liquid nitrogen bomb. Bonder and I were in the same group that did these things, so I'm surprised he didn't mention it. Procedure:

Obtain a quantity of liquid nitrogen, a sturdy soft-drink bottle (preferably 2-litre), and a ditch or something (for shrapnel protection). Fill the bottle as much as you can with nitrogen; wipe any frost off the neck, cap it extra-tight, and toss it into the ditch (or far away from people, at least). Walk casually in the other direction, and try not to laugh too maniacally when the blast comes.

Memorable incidents include the time we didn't think our 2-litre was actually going to explode; a quiet hissing noise was followed, about 15 seconds after it became inaudible, by the most impressive bang we ever got. For public demonstration, we usually put the bottle into a steel bucket (partly filled with water, for heat conduction), placed into a plastic garbage bin with the lid on. As a result, our campus physics building's roof has at least one trash can lid stranded on it.

Be careful with this one or the one using dry ice and water in ice in a soda bottle, the police (this was back in the days before 9/11 so we didn't get in any trouble we couldn't talk our way out of) gets quite angry when a soda bottle in the hands of of a homeless guy collecting bottles explodes for no apparent reason (they couldn't detect any explosives) so the public park got closed for a couple of days

Honestly, didn't think it was going to go off, it took an unusual long tome (in the magnitude of several min.)

[sparks]

Has anyone posted the one where you separate the DNA from fruit/whatever?

It works with Kiwi, bananas, and apparently liver and so on, I think, but usually a strawberry is used.

Here's a video. The step-by-step procedure is as follows:

Put a strawberry in a blender, and mash it up. I Googled and I've seen people telling you to put it in a Ziploc bag with as little air as possible and mash it through the bag. Add some dish detergent + salt + water (on the first website I saw, it tells you to use 1 cup of detergent, and 1/4 cup salt into 4.5 litres of water). Put some gauze over a cup (like, put it over the cup and tie it with a rubber band, like if you're closing a jar) and pour that mixture of the detergent/salt/water thing + strawberry that is in the blender, so that the solid bits are sifted, then take the liquid that should be in the cup and put it in a test tube (use a dropper). Add some rubbing alcohol to it, so that there are two separate layers. Something that looks like a white thread should appear and float up. That's, supposedly, DNA. A link to more accurate instructions here: http://www.imb.uq.edu.au/index.html?id=66795. If you Google a lot of other results come up.

I don't know if that's really DNA, but I've heard it claimed as being such. I recall my stepfather once saying it's not DNA per se, but not sure.

[The EGE]

I don't know if it really qualifies as a home experiment because it requires non-household chemicals, but the Briggs-Rauscher reaction is incredibly cool and a most you can buy all the ingredients at any lab-supply place.

For actual household ingredients, though, I've got a few small ones going on. Forming salt crystals from a solution and making iron oxide from a bolt in a cup of water are easy - i just leave them sitting out for a few months. I've also been growing algae for a few years in film canisters - I just filler them halfway with water, put them on my windowsill for light, and check them a few times a year.

[Zepher]

Adding Copper (II) Chloride to NaOH and yelding Cu(OH)2 and salt. (you do a double replacement reaction and get copper precipitate)

Copper (II) Chloride (CuCl2) + 2NaOH -->Cu(OH)2 + 2NaCl

It's fun because it gets really hot and produces smoke and makes the liquid look dark green and boiling for a while.

But I get the Copper (II) Chloride from the Chem. Lab at my high school because I am a lab assistant (clean stuff, prepare mass solutions for lessons, paperwork, feed snake). And I therefore get paid in chemicals that are only sold in bulk to institutions.

[The-Rabid-Monkey]

Get some Sodium Hydroxide, a glass bottle, aluminium and some balloons.
Get about a tablespoon of aluminium and put it into the glass bottle.
Cover with sodium hydroxide(s) and then put about a cup of water into the bottle.
Put balloon over top of the bottle opening.
Balloon will fill with hydrogen.
Have fun.

Also, if you get enough aluminium and sodium hydroxide in the bottle reacting, you can light the hydrogen gas coming off and it will burn for ages. my record is an hour.

WARNING: The bottle gets VERY hot. Make sure you have some water handy to immerse it into if it get above warm to OH GOD WHY IS MY HAND ON FIRE.

[Buddha]

My personal favorite is taking weapons-grade hydrogen peroxide and iodide and mixing the two. If you are to close to the reaction it will melt your face off, but if you do it right you'll get an instant cloud which you can make pretty by adding food coloring to the iodide.

[ArgonV]

taking weapons-grade hydrogen peroxide

Would that be the stuff you also use for making a piranha solution? Around 30%?