chloride in determination through argentrometric method?

The amount of chloride in water can be simply determined by titrating the collected water sample with silver nitrate solution by using potassium chromate indicator. The reaction is quantitative. The AgNO3 reacts with chloride ion in a 1:1 ratio. The result is expressed as ppm.
When silver nitrate solution is gradually added into the flask, then silver ions react with chloride ions and forms silver chloride. It is precipitated in bottom of the flask. The precipitation is white in color.
Ag+(aq) + Cl–(aq) → AgCl(s)
The end point of the titration takes place when all the chloride ions reacts and precipitated. Then slightly extra silver ions react with the chromate ions and form a brownish-red precipitate of silver chromate. The solubility product of silver chromate exceeded in the presence of additional silver ions, and then the precipitation occurs.
2Ag+ + CrO42-(aq) → Ag2CrO4(s)

Procedures:
Measure the pH of the water sample. Adjust the pH with nitric acid or sodium hydroxide, if needed.
Take a 25 ml collected water sample into a conical flask.
Add 2-3 drops potassium chromate (K2CrO4) indicator. The color of the water sample is turn into light yellow.
Add standard N/50 silver nitrate solution from the burette and shake well. Titrate until the light yellow color changes to permanent brownish-red color (bricks-red color) precipitate with white color precipitate.
Note the volume of silver nitrate added.
Repeat the titration for concordant values.
Calculate chloride ion concentration
Chloride ion concentration (mg/l) = (VSN× NSN ×35.45) ×1000/Vw
Where: VSN = volume of titrant used, NSN is normality of silver nitrate, and Vw = volume of water sample used (ml)
NB: If the collected water contains massive amount of Chloride ions such as sea water. Then it needs to be dilute into a volumetric flask.