Question

Do all necessary calculations and then in point form describe the preparation of 1.0L of a 0.25M glycine buffer at pH 9.55, given a 1.0M solution of glycine at its isoelectric point, 1.0M HCl, 1.0M NaOH, deionized water and all standard lab equipment and glassware. Show all your calculations and then put a brief lab procedure.

Answer 1

To make 1.0 L of 0.25M glycine buffer from 1.0M solution of glycine as follow-

N1V1=N2V2 ..............(1)

where N1= 0.25 M, V1= 1.0L, N2= 1.0M and V2= ?

put the value in equation 1

we get V2= 250ml

Firstly take a beaker and put 250 ml of 1.0M glycine solution and add 700ml of deionised water.

(Note: we should avoid to make final volume of 1 L initialy)

Now we get the 950ml of 0.25 M buffer of glycine.

The next step is to check the pH of this buffer solution by using given Molarity (1.0 M) of HCl and NaOH.

Adjust the pH of buffer 9.55 and add deionised water to make final volume of buffer 1L.