Sciencemadness Discussion Board

sodium carbonate: where do i buy it?

artist - 18-12-2003 at 03:26

I am working on an artwork that uses crystals growing on threads. I want to buy sodium carbonate in UK as soon as possible to test my idea out. Any idea where i can get it? my local hardware shops do not have it.
Thanks, Artist

vulture - 18-12-2003 at 03:29

Ever heard of soda? Search damnit.

sodium carbonate

Mr. Wizard - 18-12-2003 at 09:55

It can be obtained by heating common baking soda, sodium bicarbonate. (Not Baking Powder) It can also be obtained from swimming pool and spa chemical stores to balance (raise) the Ph of the water. Its also sold in the washing section of supermarkets as 'washing soda'. I'm sure there are other sources too. It is also formed when sodium hydroxide solutions react with the CO2 in the air.

sodium carbonate newbie question

artist - 28-12-2003 at 06:48

Thank you Mr Wizard. I have used standard washing soda (thanks Vulture) and it has been unsuccessful (I made a saturated solution using hot water, it was cloudy and has set in huge lumps rather than forming crystals on the threads of cotton and nylon that i hung in it). I think it's because the soda easily bought from a grocer's shop is only up to 30 per cent sodium carbonate and there is all sorts of rubbish in the mix - including wood shavings! the 'other' ingregients are not listed on the packet.

I will try a swimming pool type place (I am in London, UK so not exactly Californian in terms of proliferation of swimming pools!)

It might help if I explain what I am trying to do: I am trying to make a big tank (120cm x 60cm x 60cm) full of a clear solution that will grow crystals on a submerged structure, the structure is a tree form made from cotton threads 'woven' into a nylon grid. I am hoping the crytals grow faster on cotton threads than nylon... The solution needs to be non hazardous as it is for an art gallery... any suggestions gratefully received. Sorry for being so ignorant about chemicals (I didn't even know sodium carbonate=soda until an angry Vulture told me!)

[Edited on 28-12-2003 by artist]

Mr. Wizard - 28-12-2003 at 11:30

Artist,
I can understand the shortage of pools and such. Try looking for spa supplies, hot tubs etc. Why did you pick soda ( sodium carbonate)? It doesn't for very nice crystals. The most common substance that will grow a decent looking crystal is sugar. The crystals will be large, clear and non toxic. Soda, salt and other household chemicals tend to have inclusions, defects and look cloudy or white, even if the shape does form. Another 'common' chemical that grows beautiful crystals is Alum, (Aluminum Sulfate). I don't know where you would find it, but it isn't particulary dangerous. Salt (Sodium Chloride ) will grow large squarish crystals, but they tend to be cloudy with extra crystals stuck on.

KABOOOM(pyrojustforfun) - 30-12-2003 at 20:21

"It doesn't for very nice crystals"
but the crystals seem very artistic to me. once I had some sulfuric splash at my desck I covered the area with saturated soda solution when dry it made a very beatiful scene, strewn long needles and smaller snow-like crystals on uneven surfaces and around dusts. generally most needle like crystals make that tree like or snowish scene, eg potassium nitrate

sodium carbonate crystals

Mr. Wizard - 31-12-2003 at 08:14

Beauty is in the eye of the beholder. If Soda crystals are what you want, then I would suggest dissolving the solution in hot distilled water and filtering to removed undissolved solids and junk. Make sure the solution is close to being saturated and the let it evaporate from your container while the top is covered with a piece of cloth or paper to keep out dust and dirt. This will also slow down the evaporation, but allows for more uniform crystal growth. Some solutions form a ring around the edge that will creep up the side of the jar, this will cause a problem.

In a previous post I mentioned Alum, which is Potassium Aluminum Sulfate, not Aluminum Sulfate. Alum grows beautiful diamond shaped crystals.

[Edited on 1-1-2004 by Mr. Wizard]

choice of solution

artist - 1-1-2004 at 10:19

I chose sodium carbonate on advice from someone. But my goal is for visible crystals to appear within a wee or so (while still in the tank of solution) on the cotton threads and less crystals, or none, on the nylon thread. The tank is glass. I need the crystals to NOt form on the glass (otherwise they will obscure the structure made of suspended threads inside) I need non-hazardous chemicals, so thanks for advice, I will try out seom of your suggestions. Any other ideas gratefully received.

Organikum - 1-1-2004 at 11:15

I dont know if crystals will grow on the nylon - I rather guess no, but I am not sure on this.
Anyways, you will have to clean and degrease the surface of the fabric - a quick dip in diluted sulfuric or hydrochloric acid might do wonders, for forming small seed crystals of NaCl or NaSO4 on the fabric, inducing the grow of the crystals you want. You may dip the fabric in the acid and immediately after this dip it in a sodium carbonate solution for neutralization. Then let dry and use these "seeded" fabrics in your performance. Keeping the threads in a cold-box before you use them will also speed up crystal formation.

artist - 1-1-2004 at 11:56

Good. I do not want the crystals to grow on the nylon. Will the crystals still grow while in the solution, and be visible? If I use your idea of the sugar solution will they work in a similar way? I used distilled water in my failed experiment, can I get away with using tap water do youthink (for the sugar test) as to eventually fill the tank of 120cm x 60cm x 60cm is going to take a lot of distilled water...

Mumbles - 1-1-2004 at 19:51

I think the cashier might look at you a little funny if you go and buy 115 gallons(432 L) of distilled water. That tank is going to make a lot of crystals.

Plain tap water should be fine for sugar. We never used distilled water when we did this back in 5th grade or so. Yes, crystals will grow underwater and be visible as long as the solution is pretty close to saturation from the beginning. Too weak of a solution will greatly delay the formation. If the crystals do form on the sides of the tank and ice scraper would easily take care of it. Just scrape them to the bottom.

Organikum - 3-1-2004 at 15:32

You make the seed crystals as described on the fabric.
Fill the tank with tap water and dissolve as much soda as will dissolve.
This will take some time, stirr.
All soda MUST be dissolved.
Hang in fabric.
Crystals will grow - you will see it.

If I say time I speak from hours up to days.

Hermes_Trismegistus - 3-1-2004 at 15:51

Quote:
Originally posted by Mumbles
I think the cashier might look at you a little funny if you go and buy 115 gallons(432 L) of distilled water.


I don't know about the UK but here in Canada we buy distilled water by the "jug" from the bottled water company. They deliver, I have a monthly account with Canadian Springs here in BC and its the same price as all the other water they sell, pretty cheap indeed! And it would be pretty good to have if you are trying to grow crystals!