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

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

Notes
1. b is absent if we use Molar concentration instead of Normal as in the

case of complexometric titrations.

2. In back (residual) titration, there are 2 standards and we can
calculate the factor (F) on any one of them but it is preferred to
st
calculate it on the 1 standard.
3. The concentration of standard solutions used in volumetric analysis is

usually expressed in Molarity (M) [British Pharmacopeia “BP” and
European Pharmacopeia “EP”] or Normality (N) [United States
Pharmacopeia “USP”].

2 2n nd d S St te ep p: : C Ca al lc cu ul la at ti io on n o of f t th he e C Co on nc ce en nt tr ra at ti io on n

I In n d di ir re ec ct t t ti it tr ra at ti io on n: :

E.P . x F x 1000
Concn. = = .......... g/L
Volume taken from the sample

E.P . x F x 100
= = .......... g%
Volume taken from the sample

I In n b ba ac ck k ( (r re es si id du ua al l) ) t ti it tr ra at ti io on n: :

st
(Known excess added from 1 standard - E.P .) x F x 1000
Concn. =
Volume taken from the sample

= .......... g/L

st
(Known excess added from 1 standard - E.P .) x F x 100
=
Volume taken from the sample
= .......... g%

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