Define Sample Titration - Estimation of nitrogen and protein content?
Take the given ammonium sulfate solution into a 100 ml volumetric flask and dilute to the mark with distilled water. Mix well. Set up the steam distillation apparatus and pass steam through the apparatus for cleaning it. After the apparatus is cleaned, pipet 10 ml Tashiro's mixture into a 100 ml conical flask and place it at the delivery end of the apparatus making sure that the delivery tube is dipping in the solution. Add 10 ml of the dilute sample from the funnel in the apparatus and few drops of phenolphthalein.
After this wash the funnel with about 5 ml distilled water to ensure that all the ammonium sulphate has reached the distillation flask. Then add 10 ml of 40% NaOH and immediately close the stopper. Now heat the flask to pass the steam through this mixture. The liberated NH3 from ammonium sulphate is collected in the Tashiro's mixture in the receiving flask. Continue distillation until the level of the solution in the receiving flask becomes approximately double. Remove the receiving flask and rinse the tip of the delivery tube with distilled water. Titrate the solution in the flask against standard H2SO4 till the color changes from green to pink.