[John623]

I did an experiment in school where I put hydrogen carbonate in hot water and carbon dioxide was produced.

I assume first of all I must have used sodium hydrogen carbonate NaHCO3 since I don't think you can have HCO3 powder.

I want to make sure I am understanding the reaction.

NaHCO3(s) + H2O(l) -> Na+(aq) + HCO3-(aq)
4HCO3-(aq) -> 4CO2(g) + O2(g) +2H2O(l)

So by putting NaHCO3 in hot water you are making carbon dioxide, oxygen, and water?

Is this correct?

[Hunter2]

Not at all.

You have to put the Hydrogen carbonate in water and add some acid then you get Carbon dioxide. In hot water nothing will happen.

And in your second equation you don't balanced the charges. You have 4 minus on left and neutral on right side.

[DrCMS]

You have to put the Hydrogen carbonate in water and add some acid then you get Carbon dioxide. In hot water nothing will happen.

I agree with the first part but not the second. If you heat sodium hydrogen carbonate it disproportionates into sodium carbonate, carbon dioxide and water.  It will do that in hot water ~60-70°C.

[Hunter2]

I thought its stable. If I heat like baking cake solid hydorgncarbonate then a decomposition is observed .

[DrCMS]

We have an industrial process that uses sodium bicarbonate to keep the pH above 7 and when the batch is heated up we see a pressure rise/off gassing starting at ~60-70°C.  By the time the batch is at reflux the off gassing has stopped as I assume all the bicarb has become carbonate.  We could just buy and use sodium carbonate but it picks up moisture a lot faster than bicarb and tends to go to 25kg bricks rather than stay as a free flowing powder.  So to keep the operators happy we use bicarb.

[ikershaw]

You seem to have lost the sodium ions.

My idea would be the thermal decomposition of the hydrogen carbonate ion to the carbonate ion, water and carbon dioxide.

2NaHCO3  --> Na2CO3 + H2O + CO2

[Borek]

You seem to have lost the sodium ions.

He didn't, he get rid of them at the dissociation stage (first equation). After that they are just spectators, so there is no need to list them.

My idea would be the thermal decomposition of the hydrogen carbonate ion to the carbonate ion, water and carbon dioxide.

2NaHCO3  --> Na2CO3 + H2O + CO2

Question was about is happening in a water solution, and the original equations show that quite precisely. Your equation is more suited for the decomposition of the solid.