Page 64 - PC 101 practical notes 24-25..

MANSOURA NATIONAL UNIVERSIY
PHARM D- CLINICAL PHARMACY LEVEL I PHARM. ANAL. CHEM. I (PC 101)

P Pr ro oc ce ed du ur re e : :

E.P 1 :

1) Transfer 10 ml of the sample into a clean conical flask.

2) Add 2 drops M.O. indicator.

3) Titrate ≠ 0.1 N HCl.

{ Color change at E.P.: from Yellow to Orange }

E.P 2 :

To the above titrated solution, add 5ml neutral glycerol and 10 drops ph.ph.

indicator and then titrate ≠ 0.1 N NaOH.

Color change at E.P.:

Before titration: Orange

During titration: Yellow

At the end point: (Pink + Yellow = Orange)

ph.ph. M.O.

C Ca al lc cu ul la at ti io on ns s : :

For the first method:

Na 2B 4O 7 + 7 H 2O → 2 NaOH + 4 H 3BO 3

2 NaOH + 2 HCl → 2 NaCl + 2 H 2O
titrant

 1 Borax ≡ 2 NaOH ≡ 2 HCl

1
 1 HCl ≡ Borax
standard 2 sample
Equivalence factor (F):
1 x M.W. of borax x 0.1
each ml of 0.1 N HCl ≡ 2 ≡ .......... g borax
1 x 1000

Concentration:
E.P 1 x F x 1000
Concn. of borax = = .......... g/L
10

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