Ok, after trying multiple times swim is really confused and frustrated, he used to dissolve sodium carbonate without a problem many times in the past, now at the last stage of a limtek, for some weird reason he cant get all of the sodium carbonate to dissolve.
Neither 30g/100ml or 40g/100ml a good portion of it will dissolve, but these hard solid chunks form and refuse to dissolve even after like 20-30 minutes stirring a fine powder refuses to dissolve. This never used to happen, it would pretty well all disolve almost instantly after putting the water on, now it almost never works very well and he needs a lot of sodium carbonate water.

swim is starting to feel pretty damn incompetent, he doesnt know why he is having so much trouble with this all of a sudden, the baking soda says that its pure on the box.

Limteks use lime as a base, not sodium carb ... ?

Or which part of the tek are you using sodium carb? Which exact tek are you using, and which step are you on? Can you please be more specific?

Also I hope you do know that baking soda is not the same as sodium carb.

hah ya i know that baking soda should be put in the oven to make sodium carb.


Swim extracted the spice with limo, then mixed and separated the FASW, then he wanted to mix the sodium carbonate water to crash out the crystals. But for some reason like he said he gets hard chunks whenever he adds hot water.

well you probably added more sodium carb than the water holds? Just add excess sodium carb to warm water, shake like hell for a few minutes, let decant for a few minutes, pour away from excess decanted sodium carb, and use that water to crash out the crystals from FASW water

swim followed the recipe on the wiki here on this site for sodium carb solution, it always worked before,
though reading online it seems hard water or unfiltered water can cause calcium carbonate to form, something to do with ions and fancy jazz, so i am guessing that is what is happening.
What i think i will do if i cant get it to work now that i have a new brita filter (which is suppose to help) is i will just filter out the calcium carb, then weigh it and add a bit more sodium carb accordingly...

damn this is weird that this turning out to be the hardest part of the tek and it should be among the easiest..

ah well..

Solubility of sodium carbonate in water (Wikipedia):
7 g/100 g (0 °C)
21.6 g/100 g (20 °C)
45 g/100 g (100 °C)

Therefore dissolving 40g in water (20C) would be impossible IF your conversion (bicarbonate to carbonate) is total. Try dissolving 25g and then 20g.

I think you probably had enough sodium carb dissolve and you just dont see some dissolved. Add a couple of drops of this solution to the FASW and if it starts changing color, it means its good

Ya i was using near boiling water, at one point i was putting the sodium carbonate in the pot on the stove stirring in boiling water, some chunks still wouldnt dissolve with less then 10g/100ml

It turns out i am not crazy, it was the water, i dont know why it changed over the past few days but it must of been very heavy water. I got some distilled water and i easily dissolved 40g in 100ml. That was driving me crazy, not only would about 50% of the sodium carbonate not dissolve, if i managed to get most it gone then filtered it, white hard stuff would precipitate out of it over time, i am guessing it was calcium carbonate, but the sodium carb that did dissolve wouldnt stay dissolved. I dont know the chemistry but the distilled water worked fine, just like my tap water used to. I dont know what that was about but i was getting really frustrated i used like 2 boxes of baking soda to make sodium carb to dissolve in various ways, thinking it might react with metal pots or something, trying different containers.. god damn.. makes me wonder what the hell is in my tap water..

anyways problem solved.. finally.

Peak solubility of sodium carbonate is at 35.2degC. Boiling it just makes it dissolve a bit faster.

thats not what shoalin posted from wikipedia, anyways, the problem was not temperature, or too much sodium carb

You appear to have been mistaken in your assumption, basing it on an incomplete set of data. The wikipedia entry doesn't mention the solubilities between 20 and 100 degC. The solubility data I obtained from a solubility graph in an inorganic chemistry book. The data was posted as additional information to clarify that it's not entirely necessary to boil a solution to maximise the amount of substance dissolved. Thank you, however, for your concern.

Hardness in water supplies can change from time to time as one area may be supplied with water from several different sources.