Page 81 - PC 101 Interactive practical book
P. 81
MANSOURA NATIONAL UNIVERSIY
PHARM D- CLINICAL PHARMACY LEVEL I PHARM. ANAL. CHEM. I (PC 101)
C Ca al lc cu ul la at ti io on ns s : :
st
In this exp., the equivalence factor (F) can be calculated on 0.05 N AgNO3 (1 standard
nd
"25 ml") OR on 0.01 N NH4SCN (2 standard "titrant") but it is preferred to be calculated
on the 1 standard.
st
st
If (F) is calculated on the 1 standard (0.05 N AgNO3):
Equivalence factor (F):
1 AgNO 3 ≡ 1 NaCl
standard sample
1 x M.W. of NaCl x 0.05
each ml of 0.05 N AgNO3 ≡ ≡ .......... g NaCl
1 x 1000
Calculation of concentration:
0.05 N 0.01 N 0.05 N
[25 – 4 E.P. ( . 0 01 )] x F x 1000
Concn. = . 0 05 = .......... g/L
10
Dilution
factor
nd
If (F) is calculated on the 2 standard (0.01 N NH4SCN):
Equivalence factor (F):
1 NH 4SCN ≡ 1 NaCl
standard sample
1 x M.W. of NaCl x 0.01
each ml of 0.01 N NH 4SCN ≡ ≡ .......... g NaCl
1 x 1000
Calculation of concentration:
0.05 N 0.01 N 0.01 N
[25 ( . 0 05 ) – 4 E.P.] x F x 1000
Concn. = . 0 01 = .......... g/L
10
Dilution
factor
81 | P a g e