sodium bicarbonate to sodium carbonate

[LRGandDMT]

do i add water then heat or just heat?

 

[Jorkest]

just add heat

 

[Jorkest]

ive heard you can do it in a pot on the stove..or put it in a pan and put it in the oven at like 400 degrees

 

[GirlsHateMe]

400 degrees F for about 2 hours...

COVER THE PAN!!! unless you want a mess to clean up.

Also, just go to the laundry section of a grocery store and grab some arm and hammer super washing soda. Its like 2 bucks for 8oz. No fuss no muss, already carbonate.

 

[d*l*b]

How long should it take on the stove top?

Is there any kind of change that'll tell when the reaction has finished?

 

[downwardsfromzero]

400 degrees F for about 2 hours...

COVER THE PAN!!! unless you want a mess to clean up.

Also, just go to the laundry section of a grocery store and grab some arm and hammer super washing soda. Its like 2 bucks for 8oz. No fuss no muss, already carbonate.

Point of information: washing soda is largely sodium carbonate decahydrate. So washing soda contains up to 63% water. Roasting baking soda gives anhydrous product. This may be of relevance in dry techniques or if doing quantitative stuff.

"When crystallised from water in the ordinary way (below 32.0degC) the decahydrate Na2CO3.10H2O (soda crystals, washing soda) is formed in large transparent crystals. This salt is efflorescent, gradually forming the monohydrate when exposed to air; long exposure to air produces some bicarbonate. When heated it melts at 35degC, and on further heating deposits the monohydrate." (From "Inorganic and Theoretical Chemistry", F. Sherwood Taylor, 1956.)

 

[Jorkest]

at temps over something like 475 degrees F...it happens very very fast

 

[geeg30]

How long should it take on the stove top?

Is there any kind of change that'll tell when the reaction has finished?

Depending on how much you are converting - Swim does about 200g at a time and it takes about 5-10 mins on the stove top -you can tell when its done as it gets really fine and powdery, just remember to stir it to break up the small lumps.

The best method to tell when its done is to weigh it before and then weigh it after, it should weigh around a third less. Cant remember the correct percentage off hand but the stove top is much quicker than the oven.

 

[downwardsfromzero]

100g of baking soda should produce 73.8g of sodium carbonate monohydrate or 63g of anhydrous sodium carbonate. But it's a bit late and I did the MW's in my head.

 

[Kannamate]

boiling no water is added so how do you see it boiling maybe powder shoots up?