HS Chemistry Demo

[popjinx]

I am taking an education class in teaching lab science, and I am supposed to give a chemistry demonstration as a requirement for the course. I want to give a demo on something regarding mixtures and pure substances, separation of mixtures, or energy and energy changes. However, I am limited as to what chemicals I can use (I have no acess to lab chemicals) so the simpler the better. Can anyone give me some suggestions???

[chuinhen]

Maybe u can mix some glucose powder in to a cup of water to make a

glucose solution .

 

theres a drop in temperature of the solution !!!!

 

And u can seperate the both solution by distallation !!! 9 (but i havent try it )

[popjinx]

That is a good idea; however, I forgot to mention that, at most, I have 10 minutes to give this demo. I need something really simple.

[olmpiad]

Show the exothermic reaction of anhydrous CuSO4 and H2O, and the endothermic reaction of NH4NO3 and H2O.

[ecoli]

Something colorful would work the best for demonstration purposes.

 

I cant think of anything of hand, but there are definately compounds that change color when they come out of solution.

[woelen]

Another nice demo is the separation of a mix of iron powder and sulphur by means of a magnet. Then you mix the iron and sulphur again, put it in a test tube and heat it. At a certain point, the reaction proceeds on its own, giving a dull red heat. The iron sulfide formed cannot be separated anymore. Your mix of iron and sulphur is changed into a new chemical compound. This experiment can be done in 10 minutes, and it only requires very common chemicals like iron powder and sulphur powder. Only coarse powder is needed.

[The Thing]

Colourful demonstration, you say?

 

One cool demonstration would be mixing colourless potassium iodide and coluorless lead (II) nitrate and watch the yellow lead iodide precipitate form "almost from nowhere". Very freaky and colourful.