menu TT 04.21120. pka=4.75 21. Describe how you would prepare 250 ml of 0.2M phosphate buffer,...

Question

Question

Answer 1

Answer #1

to make 250 ml of 0.2M phosphate buffer :

reagents= Na2HPO4.2H2O

Na3PO4.H2O

1.dissolve 192.5 gm of Na2HPO4.2H2O and 67.5 gm of Na3PO4.H2O in 200 ml of water.

2. maintain PH 12.5 by adding a drop of NaOH.

3.make final volume of 250 ml by adding distilled water.

Answer 2

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