Dioctyl Sodium Sulfosuccinate VS

Dioctyl Sodium Sulphosuccinate VS; C₂₀H₃₇NaO₇S = 444.6

For a 0.01m solution Dissolve 4.5 g of dioctyl sodium sulfosuccinate in warm water, cool and dilute to 1000 mL with water.

Ascertain its exact concentration in the following manner. To 25 mL add 25 mL of a solution containing 20% w/v of anhydrous sodium sulfate and 2% w/v of sodium carbonate, 50 mL of chloroform and 1.5 mL of bromophenol blue solution and mix. Titrate with 0.01m tetrabutylammonium iodide VS until about 1 mL from the end point. Stopper the flask, shake vigorously for 2 minutes and continue the titration, in 0.05-mL increments, shaking vigorously and allowing the flask to stand for about 10 seconds after each addition. Continue the titration until a blue colour just appears in the chloroform layer. Each mL of 0.01m tetrabutylammonium iodide VS is equivalent to 4.446 mg of C₂₀H₃₇NaO₇S.