Sciencemadness Discussion Board

How long to heat NaHCO3 to make Na2CO3

KonkreteRocketry - 10-3-2013 at 06:13

How long does it take for a 200 degree hot plat to transform around 50 grams of NaHCO3 to Na2CO3 ?

Prometheus23 - 10-3-2013 at 06:45

As NaHCO3 decomposes into Na2CO3 it gives of water and carbon dioxide. You'll see puffs of gas start to be released from the powder and as the temperature rises the gas will be given off faster and faster. Eventually the production of CO2 will slow down and then eventually stop. After this happens just continue heating the sample for a little while longer to ensure it goes to completion. So you'll be able to tell when the conversion is essentially complete.

hissingnoise - 10-3-2013 at 07:21

Or, you could just buy washing soda OTC?

Hexavalent - 10-3-2013 at 09:01

Yes, but the purity of this is not always guaranteed: the washing soda here in the UK is labeled as "30%+ sodium carbonate", and, when I dissolved some in water, the mixture was cloudy, necessitating recrystallization for lab work.

vmelkon - 10-3-2013 at 16:15

I would say somewhere between 30 min to 1 hour.
I have measured the mass before and after and it works out.
I was doing this in a fireplace and once, the fire was too hot and it melted the Na2CO3 :).

Steve_hi - 12-3-2013 at 14:12

You could by quite cheaply sodium carbonate in the swimming pool supplies

metalresearcher - 13-3-2013 at 04:56

Each supermarket sells soda ash which is actually virtually pure Na2CO3.10H20.
If you want to get rid of the crystal water, just heat it to a few 100 degrees on a hotplate or stove.

vmelkon - 14-3-2013 at 18:32

Quote: Originally posted by metalresearcher  
Each supermarket sells soda ash which is actually virtually pure Na2CO3.10H20.
If you want to get rid of the crystal water, just heat it to a few 100 degrees on a hotplate or stove.


Not in Canada.
On the other hand, hardware stores and department stores that sell pool supplies sell it as a pH increaser.

elementcollector1 - 14-3-2013 at 18:34

Not in Washington either, at any rate. No 'washing soda' here, just Tide. JUST. TIDE.