So I needed a bunch of sodium carbonate, and I calculated that it would be cheaper to start with sodium bicarbonate. According to Wikipedia 200°C should do nicely:
2 NaHCO3 => Na2CO3 + CO2 + H2O
I started with 550g, and my math tells me I should expect a yield of 405g. So why did I only get 355g? The bicarbonate was perfectly dry, and I can
not find any data on any hydrates. davidfetter - 1-3-2025 at 08:45
Many things could account for what you see, to include:
"Dry" is harder to assess than you may think.
Scales are not always quite as accurate over their entire range as you may be assuming.
(unlikely) You got spots so much hotter that you may have NaOH.
Texium - 1-3-2025 at 08:52
Or... you did your math wrong.
550 g bicarbonate / 84 g/mol = 6.55 mol
6.55 / 2 = 3.27 mol carbonate expected
3.27 mol * 105.99 g/mol = 347 g sodium carbonatebnull - 1-3-2025 at 08:53
Nope, apparently I did it wrong 3 times! Jeeez, I'm getting soft.
Edit: I found it. My bicarbonate was carbon neutral with a molar weight of 72 :-D
@ bnull: We're within the limits of kitchen chemistry and scales here. But I did notice a bit of low solubility material in it so
you're probably right. Not that it matters, I'm just making sodium nitrate from calcium nitrate. The bicarbonate should do the same job, but it's low
solubility and CO2 generation would make for a messy reaction.
[Edited on 1-3-25 by Fulmen]bnull - 1-3-2025 at 15:25
