buffer query

[ashu]

please help me in explaining how to make 17mM NaOH-acetic acid buffer, pH 5.3

[Chris Pohl]

ashu,

This is from: http://www.bi.umist.ac.uk/users/mjfrbn/ ... akebuf.asp

Dissolve 1.285 g of Acetic acid (Mr = 60.05) in approx. 900 ml of pure water.

Titrate to pH 5.3 at the lab temperature of 20oC with monovalent strong base or acid as needed.

Make up volume to 1000 ml with pure water
Buffer will, of course, be pH 5.3 at 21oC

This will produce an ionic strength of 17mM and will meet your requirements if you adjust the pH with NaOH.

[HW Mueller]

It may be noted that Beynon´s (link given by Chris) other method, adding x moles of AcOH to y moles of AcO-, eliminates the inherent possibility for errors of a titration.