Sciencemadness Discussion Board

Baking Powder Versus Baking Soda

yoshiharu198 - 31-1-2013 at 04:28

You are familiar with Baking Powder and Baking Soda and can not interchange these two important cooking ingredients, even though they both cause baked good to rise.
can you suggest its chemical reaction which apply in cooking food

elementcollector1 - 31-1-2013 at 06:23

NaHCO3 -> Na2CO3 + H2O + CO2 (not balanced)

kavu - 31-1-2013 at 07:02

The main difference between baking soda and baking powder is the added sodium dihydrogenphosphate in baking powder. Both contain sodium bicarbonate which releases carbon dioxide both upon heating and in reactions with acids. The added acidic dihydrogenphosphate salt can react with bicarbonate anion in aqueous solution to produce carbon dioxide.

Lambda-Eyde - 31-1-2013 at 07:09

a) This is a spambot, ref. the other useless, gibberish posts this guy has "contributed" with. 95% possibility.
b) This is an actual person, unable to communicate properly. Nothing is lost if he's banned. 5% possibility.

bfesser - 31-1-2013 at 08:26

b) …
  i) This is a young person, possibly?
  ii) There's a significant language barrier, as they're from Tokyo, Japan, in addition to being a biology student (read as 'mentally handicapped'). 99.9999% possibility.

<strong>Lambda-Eyde</strong>, relax. At least he/she isn't another SWIM'ing cook. I'd rather put up with the clueless, than the brain-dead. Besides, if the admins banned every user who only contributes garbage, we wouldn't have an Energetic Materials section. :P

<strong>yoshiharu198</strong>, read and compare the 'ingredient(s)' labels. <a href="http://en.wikipedia.org/wiki/Baking_soda" target="_blank">Baking soda</a> <img src="../scipics/_wiki.png" /> is simply NaHCO<sub>3</sub>, whereas <a href="http://en.wikipedia.org/wiki/Baking_powder" target="_blank">baking powder</a> <img src="../scipics/_wiki.png" /> is a mixture.

[Edited on 7/9/13 by bfesser]

Endimion17 - 31-1-2013 at 08:42

Wasn't one of the baking powder's ingredients ammonium hydrogencarbonate? I don't remember those powders being acidic. They were always alkaline. Adding water would yield carbon dioxide.

bfesser - 31-1-2013 at 08:46

You're probably thinking of <em><a href="http://en.wikipedia.org/wiki/Ammonium_carbonate" target="_blank">baker's ammonia</a></em> <img src="../scipics/_wiki.png" /> (ammonium carbonate), although ingredients in baking powder do vary.

<img src="http://4.bp.blogspot.com/_Vq-FVhJjiLI/TNlUV48J3pI/AAAAAAAADMM/i3H3NT9Ui_E/s1600/baking%2Bpowder%2B059.JPG" width="300" />

[Edited on 7/9/13 by bfesser]

SM2 - 31-1-2013 at 08:56


Is "tar tar emetic" a type of raw beef which will make you blow? It would be nice to know.





OK - I do find it interesting how the CO2 comes off the heated, finely milled bicarbonate. The soda mixture physically almost behaves as a liquid. I suspect the fine milling and effects related to heat allow the solid mixture to appear this way during heating/off gassing.

blogfast25 - 31-1-2013 at 09:28

Quote: Originally posted by SM2  

OK - I do find it interesting how the CO2 comes off the heated, finely milled bicarbonate. The soda mixture physically almost behaves as a liquid. I suspect the fine milling and effects related to heat allow the solid mixture to appear this way during heating/off gassing.


The effect is similar to what's known as a 'fluid bed': finely ground solid particles through which a gas (usualy a reagent) is blown behaves a bit like a boiling liquid. In heating technology very small glass prills ('ballotini') with hot air blown through them are used to heat up stuff because the fluid bed transfers heat more quickly than hot air itself.

[Edited on 31-1-2013 by blogfast25]

Endimion17 - 31-1-2013 at 10:01

I remember being in elementary school and heating sodium hydrogencarbonate in a steel pot to obtain dry sodium carbonate.
I was mesmerized by the behaviour of the fine powder. At first, it was like a surface of a volcanic region. There was the crust and shooting geysers, but few gentle taps on the hot steel pot would turn it into a sea of powder, dancing and sloshing. It was not longer after that I've explained this as behaviour of an approximated fluid due to the tiny size of the particles, the combination of their vibrations and, way more importantly, very hot air and outgassing in the mixture. As usual, I had no one to share this with. You know the feeling... :)

The gases play the main role here. After all of the water and CO2 is gone, sodium carbonate will slosh only if there's a positive change in heating rate. If you heat the material at a constant rate, the temperature of the container stabilizes and there's little fluid behaviour. It is maximal when the temperature is increasing because the air wants to get out. So you remove the flame and let the pot cool down a bit. The air rushes back in. Then you start heating it again and you've got yourself new sloshing and geysers. It's fun to watch, but it's the best with fresh NaHCO3.

I've repeated it afterwards using dry mud. The results were the same, though the calcination yielded lots of noxious gas because of the organic matter. Later, I used the powder to make a crucible.

Powders show interesting properties as they're complex systems. Sometimes solid, sometimes liquid, sometimes even gas-like.


I'd say one could make a decent scaled model of a surface of Io or Triton using a steel plate and a burner underneath. Some nice background, a HD slow motion camera... I bet it would look a lot cooler than cheap, stupid CGI effects.

bfesser - 31-1-2013 at 10:13

The first time I heated NaHCO<sub>3</sub> to produce Na<sub>2</sub>CO<sub>3</sub>, I was so enthused by the behavior of the powder, that I sealed the product in an ampoule to keep it dry. It retains a wonderful ability to flow, to this day. I'm glad I'm not the only one who was impressed. Granular dynamics has long fascinated me.

<iframe sandbox width="560" height="315" src="http://www.youtube.com/embed/HKvc5yDhy_4" frameborder="0" allowfullscreen></iframe>
(I seem to recall requesting the paper this video is based on, some time ago.)

[edit]
It's not often that my memory is correct&hellip; <a href="viewthread.php?tid=15455&page=14#pid236639">The Paper</a>


[Edited on 1/31/13 by bfesser]

Lambda-Eyde - 31-1-2013 at 11:42

Quote: Originally posted by bfesser  
b) &hellip;
&nbsp;&nbsp;i) This is a young person, possibly?
&nbsp;&nbsp;ii) There's a significant language barrier, as they're from Tokyo, Japan, in addition to being a biology student (read as 'mentally handicapped'). 99.9999% possibility.

May be, hence the "5%" in my previous post. It is not my wish to intentionally ban users who are challenged with language.

But if you look in his fucking signature (advertising) and his first two posts there shouldn't be any doubt that this is a spambot. Bad language can't explain the nonsense in those posts. It is merely a well camouflaged spambot that uses words and expressions previously used in the thread to make it look related to the topic at hand. I've seen it earlier.

SM2 - 1-2-2013 at 08:26

off topic, but I sometimes cure my crazy glue with a liquid cold enough to cause sufficient(ly) fast contraction of the cyanoacrylate molecules to cause a local friction, and therefore, local heating, and a seed cure. Almost like local high temperatures in an ultrasonically stimulated medium. I suspect the molecules being suddenly dragged against one another, while being force compressed. The technique seems to work, but the cured glue can look nasty!

elementcollector1 - 1-2-2013 at 09:25

I've never seen my baking soda behave as described when I attempt to decompose it in the oven. What heat did you guys use to decompose the stuff?

Morgan - 1-2-2013 at 10:51

I remember making a lot of ferrous oxalate in a 3 liter flask from ferrous sulfate and oxalic acid. When heated, how interesting it was to watch the talc-like powder puff and slosh as it decomposed, dry but very fluid-like.

bfesser - 1-2-2013 at 12:25

<strong>SM2</strong>, they sell chemical 'accelerant' sprays for cyanoacrylate glues. It probably wouldn't be too difficult to synthesize the active ingredients and prepare your own.

<strong>elementcollector1</strong>, I usually only prepared a small quantity, so I heated the sodium bicarbonate in a ceramic crucible over an open flame.

zed - 1-2-2013 at 13:42

Another "Crack Cocaine" inquiry, if I have ever seen one.

Baking soda indeed! Young man, we know what you are planning to do with that stuff. Shameful!

ScienceSquirrel - 1-2-2013 at 17:32

Sodium bicarbonate really does dance if you heat it in a beaker on a hot plate as the water and carbon dioxide comes off.
I have used BP grade sodium bicarbonate and I have got a 98% yield, I guess that the product is better than 99% sodium carbonate.

ScienceSquirrel - 1-2-2013 at 17:42

Quote: Originally posted by zed  
Another "Crack Cocaine" inquiry, if I have ever seen one.

Baking soda indeed! Young man, we know what you are planning to do with that stuff. Shameful!


Benefit of the doubt?
He wants to make sodium carbonate, not phenylacetone.

blogfast25 - 2-2-2013 at 08:27

Quote: Originally posted by ScienceSquirrel  

Benefit of the doubt?
He wants to make sodium carbonate, not phenylacetone.


At a minimum I'd advise Zed not to pursue a career in the judiciary. Perhaps he agrees with a number of cases where home chemists have been suspected of nefarious purposes on the grounds of possessing a 'marked' chemical?

Suspecting someone on the basis of talking about sodium carbonate on a hobby science forum: Kafka couldn't have dreamed it up!

[Edited on 2-2-2013 by blogfast25]