In this instructable I will be demonstrating how to make a compound from a natural source and using inexpensive materials found in the kitchen. Then I will show you how to make a brilliant all time classic science class trick. You will be given step by step details of how to make a saturated solution from a home-made compound and understand how this interacts with another solvent found at home to create the final trick.....
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Step 1: Ingredients & Chemistry of Our Compound
Egg-Shells /Sand-Stone /Marble and Lime-Stone are all rich in Carbonate- Calcium Carbonate to be exact.
The area where I live, must have many thousands of years ago, been an ocean floor. Tectonics or movement of the landmass, combined with drastic climate change probably caused this ocean floor to become exposed and weathered.
Most ocean floors have a huge bed of calcium carbonate due to weathering of surrounding rock which become solubilised by carbonic acid from rains which then combines with soluable carbonate in sea-water. Of course the compacted remains of sea-shells also contributed to sea floor formation.
The molecule is so.... Ca(+II) CO3(-II)---->>>> CaCO3 - we will be carrying out an Acid/Base Reaction Neutralisation.....using acetic acid (vinegar) to make Calcium- Acetate mechanism is as follows------>>>>>
CaCO3 has two replaceable ions so we need twice as much acetic acid to our carbonate, as Vinegar has only One replaceable ion H+, which is necessary to become a complete molecule of calcium acetate. CaCO3 + 2 CH3COO- H+ ------> Ca(CH3COO)2 + CO2(g) +H2O(l)........ As simple as that ?
In the pictures above I located some white rocks which are used by children in the park to write on the pavement. This is calcium carbonate using a blunt knife we whittle it down so we have a pile of fine dust. To test take a small amount and drop into some vinegar - it should effervesce a lot.
**********Now some calculations for the amount of substance we need. *********
Please skip this stage if you are not interested in the chemistry or the laborious nature of making a compound.....As this can be purchased online......!!!!!!!,
Step 2: Necessary Weights & Measures of the Chemistry
Please bare with me if you are interested in the following rule of thumb calculation -
Pure Water has a Specific Gravity of 1 and Glacial Acetic Acid 1.045
Acetic Acid or vinegar is at 5% Wt / Vol this is not too hard to figure - % Means 100, so 5 mL of the solution is Pure Glacial Acetic Acid and the remaining is 95% water to total 100mL. But we have a 568mL of acetic acid water solution? So we must multiply by 5.68
So we have appro 28.4 mL of Acetic acid in 539.6 mL water . 28.4g / R.A.M. =28.4/60.05 = .472 Mol of acetic acid.
Why do we need to know this? So we can determine how much vinegar (acid) to react with our Calcium Carbonate. I scraped off 17gms of Carbonate it has 2 replaceable ions so we divide 17/100 as the mass of 1mol =100gms. =.017 mol X 2 as we need twice as much acid, we double this figure to .34 mol and this is how much acid we may need?
We have 1 problem how to determine how much of the bottle to use because it contains .472moles of acid .34 / .472 =.72 we multiply this with our bottle .72 X 568mL = 408.96ml .....therefore we are using 72% of a pint
Now Having worked out the amount of substance and limiting reagent necessary we can carry out the process and make our main ingredient-we measure out this (409 ml of vinegar) and place in a Glass Pyrex dish then we add our 17 gms of calcium carbonate. ------->>>>>> looking at the images----> The reaction should have produced calcium acetate-carbon dioxide & finally water. When the effervesing stops we will have a clear liquid (mother liquor', a suspension & some un-reacted chalk.
Now we siphon the clear portion (Our Product) and filter the suspension (Dirt) and leave the unreacted sediment (Silicon dioxide, Granite, Sulphate) in the bowl.
Step 3: Reducing & Drying Our Product.
Calcium Acetate Solution: We now have to somehow drive off the water and precipite the salt from solution by (Super- Saturation) However this is the laborious part and not for the faint hearted or impatient - unless you have a lab or a WW RV with a lab you are going to struggle but it is possible with basic facilities. If you had something like an massive Hair-Dryer / dehumidifier or hot greenhouse you could wait for the evaporation to complete to dryness. If not like me you will have to use a stove top! Be careful though it decomposes at 160oC.
Initially you will get it hot enough to bubble slightly and reduce the liquid substantially - however as the liquid becomes more saturated it becomes more viscous it's heat capacity increases. At some point we will end up with a crust and a skin appearing and sinking. This is a good sign - see images they pretty much show all the stages from liquid to solid. Before it gets to the putty stage the stove should be at its lowest setting, if not off.! You will see this stuff, stubbornly sticking to every part of the dish just patiently keep consolidating the mass. Using a sharp knife or small screw driver will help you scrape everything off the sides and bottom of the dish. Next step - time for some more magic....
Step 4: Preparation for the Main Event
once we have a dry powder we take about 5+gms, call it nearly a heaped teaspoon worth. We now dissolve it in the smallest amount of water 15/ 20mls it will not all dissolve as a few small lumps may be left (Poss, partial De composition?) . Now measure about 80+mls of 95+% isopropyl for a proper White snowball or if you prefer cheap n cheerful, methylated spirits is 95% alcohol poisoned with methanol. Both work very well. Guess what I used.
Now in a beaker pour the measured alcohol then take the other saturated acetate solution, whilst swirling the alcohol, pour in acetate then stop!!!, do not stir too much with a spoon or anything or you can destroy the solid alcohol suspension. Now using a stiff wire free the lump and pour excess alcohol out.
Do not be tempted to put this back in to your main bottle as its not 95% anymore probably 60%.with some acetate/water solution with in it.
Take a round shallow tin - like an empty Tuna tin, place upside down. This is your stove base for your lump of gell see images. Now set it on fire - it will burn for over 10 minutes. Well done if you have a lump of solid gell ?
Note: If you have any issues with your gel not forming it is ether too much agitation when mixing/ not enough alcohol - the proportion is somewhere around 1:5 bearing in mind this is not 100% pure......or the acetate solution was not saturated enough (Cloudy) is good a small amount of unresolved material at the bottom......!
-------->>>>>>> The Mechanism Next Chapter
Step 5: The Californian Snowball in Action
Having already made this - I like to tweak things to get less wastage of both alcohol and acetate. So I performed this twice it worked out pretty well. Considering methods, equipment and amount of patience necessary it was a worthwhile journey.
Mechanism explained.....when you make a solution the molecules of the solute (salt) and solvent (water) interact (see dissolution & solvation) to make a solution. In our case we added this solution to another solvent, alcohol, in a much smaller proportion, a lot less than the ethanol. The Calcium acetate is not soluble in alcohol, this forces the calcium acetate out of solution. As both the ethanol and a acetate dispersed when they were mixed, which causes most of the liquid becomes a thick mass like a jelly.
It's still acetate and alcohol in there as it burns to near completion leaving mostly ashes. Calcium acetate was used in the production of [Acetone] a very long time ago, this is why it also burns with the alcohol.
Also to note: The decomposition products are CO2+H2O and when all the fuel has gone we end up with Calcium Carbonate once again - I prove this by compressing the remains and putting vinegar on them.(image4&6 is video)
I hope you are not bored or disappointed maybe enlightened and maybe intrigued also
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Step 6: Concise Recipe Using 99% Rubbing Alcohol
- You can't go wrong, by following the making of the Calcium Acetate, it's of good quality. The recipe for the gell however, can be tricky if you guess the Weights & Measures. -Dissolve 6g in 18mL of water. Then add this to Either 100ml 99% Rubbing alcohol (Isopropyl) this is better for white ball, or Methylated Spirit (95%) Ethanol. A Gell should form as soon as you pour the acetate solution into the alcohol. It's does help to pre- swirl the alcohol as you pour but do not stir too much!!!!! .
Free the mass with a spoon, without breaking it up, and place on a heat-resistant base (Up-side down tin/ or on a Pyrex Glass Dish) then light with makes flame this will burn with a tall flickering flame for over 15 minutes and leave an ash residue afterwards.
When the alcohol burns it releases CO2 & H20 when the acetate decomposes it makes Carbonate & Acetone. When the acetone burns it makes more CO2 & H2O (CH3COCH3 + 5O2 ---->>>>3CO2+3H2O). The Residue Ash will react with Acetic Acid (Vinegar) and make CO2g & H20l & Calcium Acetate once Again!!!!!
***I have experimented a lot with this and isopropyl is instant and good**** Methylated \Ethanol works fine but I have found both mixes work better when they are both chilled before mixing. From a chemical point of view they are near identical alcohols, isopropyl is a third heavier than ethanol. Also isopropyl alcohol is made by the hydrogenation of Acetone (strange that - similar to our acetate when decomposing).........
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Step 7: Images of a Dancing Flame - Hypnotic
As the burn time is quite long - with the lights off it is a very impressive effect of a repetitive dancing flame...