Sciencemadness Discussion Board

Does NaHSO4 + Na2CO3 make lye and sodium sulfate?

RogueRose - 17-12-2018 at 17:50

I've never really thought of this combination and I never considered if two compounds of like ions would react but being that one is acidic and one is basic, I can't see why they wouldn't.

So the weak acid and weak base produce produce a neutral compound and a very strong (relatively) basic compound as well as a gas that can be considered acidic.
NaHSO4 + Na2CO3 -> Na2SO4 + NaOH + CO2

Is this equation correct and or would there be no reaction b/c both are sodium compounds. I never really considered reacting two compounds with like ions before for some reason.

[Edited on 12-18-2018 by RogueRose]

DraconicAcid - 17-12-2018 at 18:31

No. You will get sodium sulphate and sodium hydrogen carbonate. If you add excess sodium hydrogen sulphate, you'll get sodium sulphate, water and carbon dioxide.

HSO4(-) + CO3(2-) -> SO4(2-) + HCO3(-)

2 HSO4(-) + CO3(2-) --> 2 SO4(2-) + H2O + CO2

Vomaturge - 17-12-2018 at 18:40

In those stoichiometric amounts, it will make sodium bicarbonate and sulfate?

NaHSO4 + Na2CO3 -> Na2SO4? I'm thinking the SO4 group takes another sodium, and gives up its H+ to the more alkaline carbonate.

@ Rfear, a solution of .5mol/l H2SO4 is more acidic than 1 mol/l NaHSO4. Bisulfate salts seem to come from acids with two 'acidic' hydrogens. Typically, one of these is more powerful than the other. The more powerful one is what gets replaced in a bisulfate salt. But still, you can think of it as an acid which hasn't been completely neutralized.

Oops! Draconic beat me to it!

[Edited on 18-12-2018 by Vomaturge]

RogueRose - 17-12-2018 at 20:05

That makes sense that it would produce a bicarbonate. I didn't think I had seen this reaction before and I would think that if it did make NaOH, this would be a fairly simple way to make it and would be useful if the Na2SO4 wasn't an issue in the product. I've looked over a lot of methods to make NaOH and had never come across this, I guess that is why..

Thank you.

unionised - 18-12-2018 at 08:35

Apart from anything else, this
NaHSO4 + Na2CO3 -> Na2SO4 + NaOH + CO2
is impossible because NaOH and CO2 react.

AJKOER - 18-12-2018 at 18:26

Actually boiling aqueous sodium bicarbonate behaves like NaOH. For example, placing a piece of aluminum foil in a boiling solution of Baking Soda gives the same appearance as adding aluminum to NaOH, where on both occasions there is the production of hydrogen gas and sodium aluminate.

This is the reason that one can NOT put aluminum pots and pans into a dishwasher that commonly employ NaHCO3 as an active ingredient.

Chemistry:

HCO3- + H+ + OH- -Boiling--> H2CO3 + OH- = H2O + CO2 + OH-

and on boiling, CO2 is loss making the solution more basic.

[Edited on 19-12-2018 by AJKOER]