Hi all,
This is coming up, and I wondered if anyone had some clues to a successful prac. It's the first part, the formation of Sodium Bicarb that gives me grief. This year, I am going to try a lower concentration of ammonia (7% instead of 28%)
Any ideas would be appreciated.
Ellice.
Solvay process
Re: Solvay process
wow - I have never heard of this one.. please explain.. I would love to know..
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ellice
- Posts: 193
- Joined: 27 Jul 2007, 15:29
- Job Title: Lab technician
- School: The Illawarra Grammar School
- Suburb: Figtree
- State/Location: NSW
Re: Solvay process
Solvay process is a method of producing Sodium Carbonate .
You begin by bubbling CO2 through an ammonia/NaCl solution. I do this by adding HCl to Calcium carbonate, and bubbling the gas through ammonia soln sat'd with salt. As the reaction proceeds, sodium bicarb precipitates (supposedly!)
So you filter the reaction mixture and dry the bicarb. This is then heated strongly to convert it to Sodium carbonate. The resulting gas is bubbled through limewater to show CO2 given off. Blah blah!
I've changed the conc of ammonia, thinking a lower pH might give better results.
The set up looks impresive, even if it doesn't work!
Anyone else trying it?
Ellice.
You begin by bubbling CO2 through an ammonia/NaCl solution. I do this by adding HCl to Calcium carbonate, and bubbling the gas through ammonia soln sat'd with salt. As the reaction proceeds, sodium bicarb precipitates (supposedly!)
So you filter the reaction mixture and dry the bicarb. This is then heated strongly to convert it to Sodium carbonate. The resulting gas is bubbled through limewater to show CO2 given off. Blah blah!
I've changed the conc of ammonia, thinking a lower pH might give better results.
The set up looks impresive, even if it doesn't work!
Anyone else trying it?
Ellice.
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ELIZABETH
- Posts: 233
- Joined: 02 Jun 2006, 10:00
- School: O'Connor Catholic College
- Suburb: Armidale
- State/Location: NSW
Re: Solvay process
Tried it some years back- had a lot of fun setting it up and doing it, but very little product!
Liz
Liz
Re: Solvay process
Yes, doing it next week. I use 18%NH3 solution, but as you say, with limited success. Kids love the set up.
Lada
Lada
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ellice
- Posts: 193
- Joined: 27 Jul 2007, 15:29
- Job Title: Lab technician
- School: The Illawarra Grammar School
- Suburb: Figtree
- State/Location: NSW
Re: Solvay process
STOP PRESS
Bubbling away most of yesterday, (not me, the CO2!!) and had a good result. Lots of powdery stuff that looks like sodium bicarb if you use your imagination.
For those giving this prac a try, I used 3M HCL, lots of. Kept replenishing the marble chips . The ammonia soln was 7% .
I'll keep the one I've done, and at the appropriate minute, present it, "and here is one I prepared earlier".
Good luck.
Ellice.
Bubbling away most of yesterday, (not me, the CO2!!) and had a good result. Lots of powdery stuff that looks like sodium bicarb if you use your imagination.
For those giving this prac a try, I used 3M HCL, lots of. Kept replenishing the marble chips . The ammonia soln was 7% .
I'll keep the one I've done, and at the appropriate minute, present it, "and here is one I prepared earlier".
Good luck.
Ellice.
