People, (oops, I meant to add a "2" after the Na in title)

 

Say one has a 50lb bag of sodium hydroxide pellets, saved for 5 years. Then, say it turns into a solid rock. Then , say one smashed the rock into bits and dissolved the whole mass. In your opinions, how much of the NaOH would have absorbed carbonates from the atmosphere ? When that happens, is it part of the NaOH converting to carbonates, or is it the NaOH is still there and just that the carbonates are adhering/adsorbing onto the NaOH pellet's surface?

 

Thanks!

Oh- if it "converts", is it likely that the entire NaOH can convert over to be fully Na2CO3?

Edited January 26, 201312 yr by pippo

NaOH stored in the atmosphere for 5 years? Very much of it has reacted, I'd say.

 

From previous observation, NaOH first absorbs air moisture - at least in temperate climate - to form a paste. If your thing is dry and hard now, it could well be that absolutely all NaOH is converted into Na₂CO₃ or NaHCO₃.

 

Smash some and try to dissolve: Na₂CO₃ doesn't, NaHCO₃ and (mind the heat) NaOH do. Use pH paper, cheap and available, to see if it's still any alkaline.

 

But if you know the initial weight, you could just compare.

My guess, and it's no more than a guess, is that there will still be some NaOH in the middle.

I don't know how Enthalpy thinks Na2CO3 doesn't dissolve: it does.

 

(Edited- typo- my bad)

Edited February 7, 201312 yr by John Cuthber

I mistook it for CaCO₃. My bad, sorry.

sorry for late reply, people, but yeah, turned out MOST of the NaOH was still "there". I titrated BOTH the carbonate and the hydroxide, and the carbonate was minimal. Looks like most of the NaOH was "preserved". Big Thanks for the help.