practical chem 101
I have a scale which can mease up to 0.001g, but it only gets effective when you measure +50mg, so it's not very usefull with lower doses. I can say i can measure 75mg with a range of + or -5 mg.
Well alright then, good that you have a scale to determine the mass for yourself. If the scale "creeps" which is what you probably mean by not being effective at low doses, why don't you use something that is > 50 mg to start with?
Luckily my cheap ass 0.001 scale that was 6 times as cheap as my 0.005 lab-scale (with a big plastic dome and everything) doesn't creep even at low doses. But if it does why not put on something that serves as a sort of miniature plate and weigh your powder accurately on that?
(sidenote: Labs have weighing papers and weighing 'cups' for that purpose. I fold a square diagonally so that you can fold it and not spill anything. Good weighing paper or ponypacks are made of wax-coated paper. Probably available on the internet for you if you plan on experimenting with powders a hobby, I bought them in a smartshop which is like a headshop only they sell ethnobotanics and legal drugs in my country. My 0.001 scale has a little plastic plate that is ideal honestly!)
Still, liquid measurement increases your accuracy by the order of magnitude you start with. So 75 mg can be measured 75x as well that way (unless my logic is flawed) so I recommend it.
Is it better to use demineralized water??
I'd say yes, almost always. It's more significant when you do chemical reactions, especially sensitive ones, but for storage of a chemical it might increase your shelflife because there are no minerals in it that might help bacteria to grow.
When the 2cb is dissolved i will store it in a fridge! how long can i store it then?
It's really very hard to say. Sometimes there are very little germs in there that may germinate into flakes of bacteria or mold, and sometimes there are. But this is why I said this:
Make sure nothing lays on the bottom if you plan on using water. Here's why: water can contaminate with bacteria / mold or whatever.
Well I didn't finish that thought: you should make sure everything is dissolved well and nothing is laying on the bottom because later on after you have kept it for a while you can test if the solution is still okay by swirling it. If you see stuff swirling up in the liquid that had been laying on the bottom then it's probably bacteria and you shouldn't take it.
So.... if you start with sediments already laying in the bottom you won't know what is what!
You mean that i should put it in vodka so i don't have to put it in the fridge and i can store it for months, maybe years?
Exactly. The higher the alcohol % the better it will keep. Above 15-20% is generally good enough but more is even better.
How many years will it be okay theoretically? Hell again, hard to say. Perhaps something can live in alcoholic liquids? Make sure you don't expose your solution more to the outside world then necessary although with alcohol that's merely general precaution.
Does the alcohol have any effect on the 2cb itself?
The alcohol doesn't affect the 2C-B but if you have very low concentrations then the alcohol obviously affects
you and your trip. That's all. 2C-B is quite stable, it is said pretty much all or most phenethylamines are. There are stable enough tryptamines as well but less so in general. 4-HO tryptamines are notoriously sensitive.
is it hard / nessecary to dillute the vodka?
Diluting vodka is as easy as measuring half or more of the volume with vodka and adding it up to the total volume with water. In your case 25 ml total. So 15 ml vodka and 10 ml water is probably what I would do as a rule of thumb, although making it all 25 ml vodka is no waste IMO. So maybe that's better.
Is it necessary? Already covered that.
) and you can find a whole thread on it 
