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Has anyone out there in our loverly labland done the Elephant toothpast experiment yet. I have lots of ways to do it off the internet but was wondering if there was any tried and tested best ways of doing it.
we are going to try this so any ideas would be great .
Could be quiet fun but quiet messy I have that feeling .


thanks heaps
Kimmy

Hi, I've (hopefully) attached the procedure we have used. It comes from "Flinn Scientific" website.
We only ever did it as a demonstration due to 30% hydrogen peroxide being used which is pretty nasty stuff.
It always worked and impressed the kids.
cheers
jen

thanks that sounds just like what i am after.
thanks again.

Kimmy

Hey Kimmy,

I do it often, but never so precisely.

30% peroxide in a large measuring cylinder, a good squirt of conc dishwashing liquid, and add a spatula full of KI. Stand back! Don't be tempted to touch the resulting foam, as it can burn, especially at the fingernails!!! However, the foam goes and goes and goes, so it's very impressive.

If you WARM a little peroxide, put it in a little measuring cylinder (plastic is best) and add a drop of dishwash and a few crystals of KI (KI is always last) it goes BANG! as the oxygen is released simutaneously from the H2O2 all at once.

Hi
I also put a couple of drops of different dye colours around the rim of the cylinder,so that when it rises,it makes striped toothpaste and also put it in a large tray if possible, to help with the cleaning up later!
Rhonda

Oh hey, I'm going to try that too!

Hi All
Great one can't wait to try them
Thanks
Noona

have tried and they are great thanks the kids will love - must admit I have only tried with teachers in prep room yet. Will do with students this week.

thanks again

KIMMY

With the warmed one that goes 'BANG'... is a glass measuring cylinder ok to use for that or will it break?

I'm doing this for stage 2 (about 75 kids) on Friday morning so I'll probably be using my big 2L cylinder so they can all see. Any advice from those of you who have done it plenty of times? I am going to have some practice runs in the lab in smaller cylinders but don't want to waste too much of everything.

hi everyone...and welcome back to all of you from NSW....anyway...yes we do this prac alot and also do it for our open nite...the kids just think its fantastic.The only advice i would give you is to put the 2litre cylinder in a tub or low sided buket only because when it goes off the overflow goes everywhere.Have fun
Matchstick

OK so i've been experimenting with 500ml cylinders and I think I'll go with that because I have lots of them and can have a few goes with putting food colouring in one, having a hot and a cold one etc... but when I do it, I don't get anything dramatic like the ones on the internet. It just slowly fills the cylinder and then oozes over the side when it gets to the top. Is it my detergent? or not enough H₂O₂? I tried it cold from the fridge and one left in the sun to warm up and then in hot water (i dont have a microwave). Is there something else I should try?

or is it because I used solid KI instead of dissolving it first? I'll go and try that...

i love the striped toothpaste idea will have to give that a go i think .

Sorry for the running commentary on my results... but I want to know it will work when i have about 75 kids plus all their teachers watching!

I tried using a 100ml cylinder (to use less), let the cylinder sit in hot water for a while, and also dissolved the KI in hot water. i bought some morning fresh concentrate in case my bulk supply detergent wasn't quite good enough. I got a much faster reaction this time around, but still not as dramatic as I've seen. Although after all these posts I've realised everyone else uses 30% and I'm only using 6% because that's all we have here. That probably explains it...

Any Tamworth labbies out there have stronger H2O2 I could borrow to use and replace when I do my next order?

Hi All,

Just wondering , I only have 35% hydrogen peroxide would this make a huge difference ?????? Don't want to blow mysel up

Sammy

I looked up QStores to see if I could order a stronger solution (obviously not by Friday) and they only sell 35%, 6% and 3%. I can't imagine the difference between 30% and 35% would make it dangerous, just maybe a bit more spectacular!

Just did experiment using the 35% Hydrogen Peroide and worked a treat
Thanks for a great little experiment and might I say the first one I have done from start to finish by myself Yay

Gotta Love being a Labbie ! We have all the fun


sammy

Rosalie,

A 2L cylinder can almost be too big! A 500mL or even 250mL has a narrower opening, so the foam goes up more, and looks more impressive. The wider the jar, the less spectacular the effect.

Carpet cleaning companies have VERY strong H2O2, at 50%. I begged a little jar from a local bloke. You know the lines: "help out the school etc etc".

And yes, I do use plastic. And PLEEEEEZE remember not to let the darlings play with the exciting foam. It burns your skin and invades your fingernails and hurts for hours. I know this from personal experience.

Good Luck.

Thanks Smiley,
I'll see what I can do I've told the teacher I can't get the supplies till next week so we'll be doing the Mentos and Diet Coke one tomorrow, and I'll do the elephant's toothpaste next Friday. I might ring a few carpet cleaners, or even ask if there is one attached to the school or which one the school uses when our carpets get done Perhaps they even have some in the maintenance shed!

I have one of our maintenance guys making a contraption for delivering the mentos into the bottle which I need to try out this arvo. I've got one of those plastic things that you use for tornado in a bottle (the bit that connects the 2 bottles together) and I found a metal pipe that fits in the other end and he is welding some metal onto the top of the tube so it has a smaller hole to come out.

I am having so much fun with all this this week!! Any with nearly every class starting new topics I haven't had many pracs to worry about, so it has worked out well that I've had time to experiment with these ones before going in front of the class. This is why I love science!!
Rosalie