Transcript Slide 1

Color Changes for the titration of
NaCl  AgNO3
using K2CrO4 indicator
(Mohr’s Method)
Note: Actual colors in the lab may vary somewhat from what is shown. These pictures are intended as a rough guide
only.
Before starting
titration
Cl- sample
+ CrO4-- ind.

Clear Bright
Yellow Soln.

X
During titration
(AgCl is formed)
End Point
Just after
the end point
Cl- sample
+ CrO4-- ind.
+ AgCl ppt
CrO4-- ind.
+ AgCl ppt
+
few
Ag2CrO4 ppt
CrO4-- ind.
+ AgCl ppt
+ Excess
Ag2CrO4 ppt

Turbid Bright
Yellow Soln.

Turbid Dark
Yellow Soln.
The same Color Changes occur
during the titration of
NaBr  AgNO3
using K2CrO4 indicator
(Mohr’s Method)
Color Changes for the titration of
NaCl  AgNO3
using Fluorescein indicator
(Fajan’s Method)
Note: Actual colors in the lab may vary somewhat from what is shown. These pictures are intended as a rough guide
only.
[A] During titration
(before E.P.)
[B] 1st drop excess of AgNO3
immediately after the E.P.
White ppt in
green fluorescence
Pink ppt
in faint colored solution