Laborant got a task to make a buffer, which pH = 8.00. Which same concentration solutions and which ratio would you suggest him to mix?
4 answers
This must be part of another series of questions since it refers to "same concentration solutions". As it stands we don't know the whole problem.
No, it's all problem. Well the end is: search all constants in internet and books
If that's all of it then your prof didn't give very good directions. I have no idea which acid he/she has in mind so I'll fly blind. I looked at the Ka values and picked HOCl.
With pH = 8 for a buffer I might pick HOCl for the acid with Ka = 3.0E-8 (you need to see what that number is in your text and use it) so pKa = 7.52.
Use the Henderson-Hasselbalch equation and solve for B/A ratio. I obtained b/a = 3.02. To prepare 1 L of buffer I would mix 5.0 mols HOCl and 15.1 mols NaOCl. You can convert to grams of each if you wish. I still think the prof had some concn in mind.If this is a biochemistry class you may want to look at the TRIS and other biochem buffers that ae used. Those (or the phosphate buffes) may be better suited for that purpose.
With pH = 8 for a buffer I might pick HOCl for the acid with Ka = 3.0E-8 (you need to see what that number is in your text and use it) so pKa = 7.52.
Use the Henderson-Hasselbalch equation and solve for B/A ratio. I obtained b/a = 3.02. To prepare 1 L of buffer I would mix 5.0 mols HOCl and 15.1 mols NaOCl. You can convert to grams of each if you wish. I still think the prof had some concn in mind.If this is a biochemistry class you may want to look at the TRIS and other biochem buffers that ae used. Those (or the phosphate buffes) may be better suited for that purpose.
Thank you very much for the help! Now I see what should I do.
0 answers