reidy2015
Harmless
Posts: 23
Registered: 14-3-2015
Member Is Offline
Mood: No Mood
|
|
1N koh preparation
How to prepare 1N KOH need help please to understand how to do this .
[Edited on 15-03-2015 by reidy2015]
[Edited on 15-03-2015 by reidy2015]
|
|
|
Nicodem
|
Thread Moved
22-3-2015 at 01:54 |
morganbw
National Hazard
Posts: 561
Registered: 23-11-2014
Member Is Offline
Mood: No Mood
|
|
Find its molar mass. Add this in grams to enough H2O to make 1 liter of solution. This is the simple answer.
You can use a small amount of math to make whatever quantity you need.
This answer is based on pure KOH.
This is also a 1M solution but be aware that 1M solutions are not always equal to a 1N solution.
[Edited on 22-3-2015 by morganbw]
|
|
|
gdflp
Super Moderator
Posts: 1320
Registered: 14-2-2014
Location: NY, USA
Member Is Offline
Mood: Staring at code
|
|
How accurate does the concentration need to be? If it just needs to be approximately 1N, then the above answer is correct, however almost all KOH
contains at least 10% due to it's extreme hygroscopicity, though some contains significantly more. If you need it to be reasonably accurate, then you
should make up a solution accounting for the fact that every 10g of solid only contains up to 9g of KOH, then titrate the solution with a known
concentration of acid to find the actual concentration.
|
|
|
morganbw
National Hazard
Posts: 561
Registered: 23-11-2014
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by gdflp  | | How accurate does the concentration need to be? If it just needs to be approximately 1N, then the above answer is correct, however almost all KOH
contains at least 10% due to it's extreme hygroscopicity, though some contains significantly more. If you need it to be reasonably accurate, then you
should make up a solution accounting for the fact that every 10g of solid only contains up to 9g of KOH, then titrate the solution with a known
concentration of acid to find the actual concentration. |
Agree in total.
That is why I stated my answer as based on pure KOH.
|
|
|
Molecular Manipulations
Hazard to Others
Posts: 447
Registered: 17-12-2014
Location: The Garden of Eden
Member Is Offline
Mood: High on forbidden fruit
|
|
Pure potassium hydroxide can be had by fusing tech. grade KOH in a nickel crucible at over 300 degrees C.
-The manipulator
We are all here on earth to help others; what on earth the others are here for I don't know. -W. H. Auden
|
|
|
morganbw
National Hazard
Posts: 561
Registered: 23-11-2014
Member Is Offline
Mood: No Mood
|
|
This takes care of the Potassium carbonate as well?
|
|
|
Molecular Manipulations
Hazard to Others
Posts: 447
Registered: 17-12-2014
Location: The Garden of Eden
Member Is Offline
Mood: High on forbidden fruit
|
|
Nope, carbonate doesn't decompose at standard pressure. It boils at around 1600 degrees C decomposing into potassium and oxide ions and carbon
dioxide, which reform carbonate on cooling. There's nothing you can really do about carbonate once you've got it.
-The manipulator
We are all here on earth to help others; what on earth the others are here for I don't know. -W. H. Auden
|
|
|
reidy2015
Harmless
Posts: 23
Registered: 14-3-2015
Member Is Offline
Mood: No Mood
|
|
Thanks 
|
|
|
Hawkguy
Hazard to Others
Posts: 326
Registered: 10-10-2014
Location: British Columbia (Canada eh!)
Member Is Offline
Mood: Body is Ready
|
|
Can't you spray Nitrogen or Argon to purge the Carbon Dioxide?
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
