Apparatus :

1Test Tube
1 Titrator

Reagents :

Chloride Reagent no1 (15ml )
Chloride Reagent no 2 (100ml)
Phenolphthalein Reagent (15ml)
Sulphuric Acid Reagent (0.5 N.) (15ml)

Procedure :

1. Fill the Test Tube to 15 ml level with water sample.
2. Add one drop of Phenolphthalein Reagent to the sample. If the solution remains colourless proceed directly to step 3. If the sample turns red, add Sulphuric Acid one drop at a time until the red colour disappears. Then proceed to step 3.
3. Add three drops of the Chloride Reagent No.1 to the sample in the Test Tube. Insert the Test Tube Cap and shake to mix. A yellow colour will result.
4. Fill Titrator with the Chloride Reagent No. 2 to the 'Zero' mark in the Test Tube Cap. Then add to sample drop by drop, shaking gently, until the yellow colour is permanently changed to pink / brown.
5. Result is obtained in p.p.m. Chloride by multiplying Titrator reading by 10.