triboluminescence so we decided to have a go at making it and seeing if we could capture it

on camera. We start with 10 grams of anthranilic acid which we oven dried for several hours before

use. You can find out how to make this in our other video linked here. We transferred the

anthranilic acid into a 100 milliliters flat bottomed flask. The flask needs to be big enough

to allow some internal reflux so a 250 ml flask or conical flask would also work well. Next measure

out 25 ml of acetic anhydride. You can find out how to make this in another of our videos linked

here. Add the acetic anhydride to the flask containing the anthranilic acid. You will start

doing this to make sure that the acid is absorbed by an anthranilic acid. Now condensed winners,

to see the anthranilic acid dissolve. Then with swirling, the contents will suddenly

turn solid. The mixture heats up and the solids dissolve

again forming a red solution. Swirl the flask and you should see everything

dissolve back into solution. The flask at this point is quite warm.

Place the flask on a hot plate and heat it. You want to get to a very low boil where the

refluxing on the inside of the flask. Here we go.

Keep this going for 10 minutes and then switch off the heat and allow the flask to cool.

As you can see, we got quite a good reflux going, but with no vapor escaping from the

flask because the anhydride has a high boiling point.

Now measure out 8 mls of water.

When you're done with the refluxing process, you should see the flask at this point. You

40 to 50 degrees C add the water to the flask swirl the flask and you can see

that the contents heat up again with a little bit of reflux starting up on the

sides now put the flask back on the hot plate and heat it until it reaches a

boil then remove the flask and place it somewhere undisturbed for a few hours in

and for crystals to form soon you should get some very nice white crystals

growing out of the solution this is our product and acetyl anthranilic acid

beautiful we chilled the mixture for another few hours to see if we could get

more crystals then it's filter time and we need to be as delicate as possible so

as not to damage our crystals

we left these on the pump for a good 20 minutes in order to get all the liquid

off in the meantime we prepared 20 mils of ice-cold methanol

we use this to rinse out their reaction flask and then gently wash the crystals

on the filter we did notice that a small amount of product dissolved in the

methanol

even though it was ice cold we're not sure if any other solvents are suitable

here though but be careful at this stage again we left the product on the pump

until it was completely dry

here's our product 11.7 grams of crystalline and acetyl anthranilic acid

this is a ninety percent yield on starting and morbid acid which is great

we place the sample

these crystals between two glass plates and crushed them in a dark room but we

couldn't see any flashes of light we figured that maybe they needed to be

drier so we placed them into an oven at 100 degrees C for an hour

here's our perfectly dry crystals again we placed some on a glass dish and

prepared another dish that we could use to crush the crystals

nothing either for the camera or for the naked eye

so we're not too sure about this one we'll have a go at recrystallizing the

product and seeing if we can get it to work with a very large single crystal if

anyone knows how to get this to work then please let us know

you

stay tuned