I'm a science teacher at an upper elementary looking for some fresh ideas as for what fun, and preferably educational, stuff to do with students. Got a shitload of potassium in different forms and other chemicals but no stuff like high voltage devices or liquid nitrogen.
Mainly looking for chemistry ideas.
Suggestions?
>>7916457
bump
>>7916457
I would recommend not giving elemental potassium to children.
>>7916457
Add a few ml of sulfuric acid to a test tube or ignition flask. Carefully pipette an equal amount of ethanol on top of that. You should see an interface. Drop some potassium permanganate into the tube, a few grains will do. Make sure the tube is in fume hood and secured to a ring stand. The acid generates ozone from the permanganate which oxidizes instantly in ethanol. Generates a lot of heat so don't touch the tube.
Anyone have the crystal-making infographic?
Me and my wife's son tried it the other week and had loads of fun
>>7916457
CP violations are where its at, all the kids want in on that
>>7916711
I'll try that out tomorrow. Creating ozone sounds like fun!
>>7916711
Btw, any particular concentration of ethanol/sulphuric acid? Got about 95%.
To demonstrate thatwater is polar:
Let a gentle but steady stream of water flow from a spigot. Vigorously rub a glass rod with a piece of wool or fleece. Place the glass rod next to the stream of water. The water will be attracted to the static electric charge on the glass rod.
Identify what metal element is in a salt.
If you have several different ionic salts...
Dip a q-tip into some water or hydrochloric acid.
Then dip the end of the q-tip into a sample of the salt.
Place the salt on the end of the q-tip in to a flame.
The flame will change color based upon what metal ion is in the salt.
Strontium, calcium: bright red
Sodium: pumpkin orange
Potassium: light lavender and sparkles
Copper: fluorescent green
This is a very simple experiment that doesn't require a lot in the way of resources.
BE CERTAIN to position the flame horizontally--you can use a clamp and a ring stand to do this. Otherwise, the chemicals will drop off the q-tip into the flame thus contaminating the flame color.
Kids and even adults love this.
Plus, you can explain that this is the same basis for producing some of the colors in fireworks.
Place the salt
>>7916896
Highest you can get. It is fun. Better with the room lights off. Ozone will oxidize at the interface in small bursts. It make small visible and audible pops. Do not substitute the ethanol for acetone or methanol. Way too violent.
Throw a live pig into a vat of concentrated acid.
For education.
>>7916717
You made it all the way from r9k did you?
>>7917561
Ahahahhahaha
>>7916717
>my wife's son
You mean your own son?
>>7917715
He's more like a stepson
I love him like my own though
for upper elementary you can teach them some flight stuff. kids love airplanes.
Dissect a cat in front of class.
>>7917769
>>7917788
I'm not sure what this is illustrating but I'm American...
>>7916457
Mix potassium ferrocyanate with phosphoric acid, the gas created smells lovely.
>>7917820
Kek
Baking soda and vinegar.
Drip a little Iodine onto starch. Observe it become blue.
Explain that the fluid only turns blue when in contact with starch, by dripping some of it onto other substances and observing it stay the same colour.
Then spit on the starch and observe the Iodine turn back to it's original colour.
Let them guess what happened.
Pro tip: your spit split the starch into sugar. This will teach them to always chew properly.
elephant toothpaste with manganese dioxide and 30% hydrogen peroxide
>>7916888
what actually happens is that the sulfuric acid turns the permanganate into permanganic acid and dehydrates it into manganese heptoxide. adding ethanol will result in an explosion since Mn2O7 is a very powerful oxidizer
H2SO4 + 2 KMnO4 = Mn2O7 + K2SO4 + H2O
>>7918528
That is pretty close, but it isn't quite right. There are actually two distict reactions happening:
6 KMnO4(aq) + 9 H2SO4(aq) → 6 MnSO4(aq) + 3 K2SO4(aq) + 9 H2O(l) + 5 O3(g)
This shows the formation of the ozone as a byproduct of the initial interaction of permanganate and sulfuric acid:
C2H5OH(l) + 2O3(g) → 2CO2(g) + 3H2O(l)
And that is the follow up cumbustion reaction. The second reaction that is occuring is pretty much what you are showing. Manganese heptoxide does form is minute quantity:
2 KMnO4(aq) + 2 H2SO4(aq) → Mn2O7(aq) + H2O(l) + 2 KHSO4(aq)
Only a slight vaiation of the products which were confirmed via GC/MS and FT/IR. The oxidation of those products follows:
4 Mn2O7(aq) → 8 MnO2(aq) + 3 O2(g) + 2 O3(g)
And that is what is really happening. It is far more complicated than I was letting on with just the O3. Please don't try to isolate the manganese heptoxide though. I blew up so much good lab glass doing that experiment.
Thermite - just need some aluminium powder and iron oxide. Set it behind a perspex screen on a flowerpot filled with sand. It's good fun.
