[eurekah]

Alright so I am in a chemistry class at the moment and we are all required to do a science demonstration involving one of the elements.  Now I would like to do something that could in involve explotions, flashes of light, fire, that kinda cool stuff, but nothing to big. 

What i was thinking of is make a colourfull smoke bomb.  I know that saltpeter forms a lto of gas when ignited, so I was thinking  of making one of these but have a mixture of various other materials layered in the saltpeter, so when it burns through each layer a diffrent color is formed....but i would like to try something else.

Anyone got any ideas?? My Chemistry teacher is a fairly interesting person that will pretty much allow anything as long as it doesn't cause too much damage....
thanks

[mike]

Does the demonstration have to be with an element?

You could burn magnesium (Mg) ribbons in a bunsen burner flame (safety: goggles, lab coat, lots of heat prodcued, very bright, do not look directly at flame as UV light emitted.)

Sodium (Na) in water (safety: goggles, lab coat, gloves)

Flame tests.

[eurekah]

I was talking to him today and he said it doesnt specificaly have to be a single element, so i am open to any experiment pretty much....

[wereworm73]

How about a little ammonium triiodide?  Small amounts of it are sometimes used in school demonstrations, and it doesn't take much to make it explode. You'll have to make it on the spot because it's extremely likely to explode prematurely if you try to store it.

[eurekah]

is that the stuff that if you apply pressure to it, it goes off?? i remeber last years sciences class was laying that stuff in the hallway and passer byers would crap their pants when a big bang happens....

[Borek]

Don't even try, sounds funny, but it is too easy to loose a finger or two.

[Kenichi]

Reactions such as aluminum or sodium with iodine are always fun.  Take iodine crystals and powdered aluminum and then after mixing them together drop some water on it.  Tricycloacetone peroxide is also a fun and easy project. But, not only is it VERY unsafe and almost as sensitive ase the ammonium triodide, your teacher might not want it's synthesis to become common knowledge. As noted before by Mike, flame tests are also pretty. 
  Another idea is to take a couple of pennies and cut them so the zinc inside them is exposed.  Drop them into a test tube with hydrochloric acid (6M is what i used) and then cover the top of the test tube with a balloon.  After collecting the Hydrogen gas which is liberated in the reaction of the zinc and hydrochloric acid you can tie off the end of your balloon and attach it to the end of a stick.  Light a candle on a desk far from any student and then, using the stick, maneuver the balloon over the candle.  boom.

[Kenichi]

Aluminum foil can be substituted for the zinc in case there is an issue over the defacing of currency.

[woelen]

Spectalular reactions invoving two elements. Not too big, but very nice:

http://woelen.scheikunde.net/science/chem/exps/Al+Br2/index.html
http://woelen.scheikunde.net/science/chem/exps/Cl+I/index.html
http://woelen.scheikunde.net/science/chem/exps/mg+iodine/index.html
http://woelen.scheikunde.net/science/chem/exps/P+Br2+Cl2/index.html

[tennis freak]

a couple of demonstrations that my teacher did for our class were:

pouring a little bit of ethanol in one of those giant office water bottle things and then dropping in a match.

The second was filling a balloon with a bit of hydrogen and then putting a candle on a stick near it causing an explosion.

However i do not suggest or promote doing these experiments unless supervised by a professional or if you know what you are doing. A little simpler would be to take mentos and dump them into a 2 liter bottle of coke or something causing a fountain

[syko sykes]

flame tests are always good, use different elements such as copper, sodium, etc. to get different colors

or get 2 rusty iron balls, wrap one in aluminum foil and bang them together to make a spark

http://www.chemicalforums.com/index.php?PHPSESSID=76730bdb5e1a3b30fbc561ee4bb3ceab&topic=8401.msg39375
that topic should give you some more info on the mentos in coke idea

or put some crystalline KClO₄ in a test tube and heat it over a fire until it turns liquid. then drop a gummy bear in and watch the fun. a cheetoh is said to work well too. this should probably be done in a hood though.

[insert disclaimer here]

[mike]

or get 2 rusty iron balls, wrap one in aluminum foil and bang them together to make a spark

Similar to thermite reaction?

[syko sykes]

or get 2 rusty iron balls, wrap one in aluminum foil and bang them together to make a spark

Similar to thermite reaction?

probably similar but on a much smaller scale... i don't think they owuld be too happy with a student doing the thermite reaction in a classroom.

[mrdeadman]

or get 2 rusty iron balls, wrap one in aluminum foil and bang them together to make a spark

Similar to thermite reaction?

it's not that insane like a thermite reaction, all it does is spark.
superoxidizer+gummybears ftw!

[mike]

But is it the same reaction as the thermite reaction? I was just wondering what the science behind it was, ie what is the significance of the rust (iron oxide) and aluminum foil? Sounds like the same ingredients for thermite to me..