Determination of Esters : Pharmaguideline -->

Editable Pharmaceutical Documents in MS-Word Format


Determination of Esters

Learn how to determine the Esters in Pharmaceutical preparations.
Boil a convenient quantity of ethanol (95 percent) thoroughly to expel carbon dioxide and neutralize it to phenolphthalein solution. Unless otherwise stated in the individual monograph, weigh accurately about 2 g or other suitable quantity of the substance under examination so that the volume of 0.5 M ethanolic potassium hydroxide added is at least twice that theoretically required, dissolve it in 5 ml of the neutralised ethanol contained in a hard-glass flask and neutralise the free acid in the solution with 0.1 M ethanolic potassium hydroxide using 0.2 ml of phenolphthalein solution as indicator. Add 25.0 ml of 0.5 M ethanolic potassium hydroxide and boil under a reflux condenser on a water-bath for 1 hour. Add 20 ml of water and titrate the excess of alkali with 0.5 M hydrochloric acid using a further 0.2 ml of phenolphthalein solution as indicator. Repeat the operation without the substance under examination. The difference between the titrations represents the alkali required to saponify the esters.

Ankur Choudhary is India's first professional pharmaceutical blogger, author and founder of, a widely-read pharmaceutical blog since 2008. Sign-up for the free email updates for your daily dose of pharmaceutical tips.
.moc.enilediugamrahp@ofni :liamENeed Help: Ask Question

No comments: Read Comment Policy ▼

Post a Comment

Please don't spam. Comments having links would not be published.

Popular Categories

QA SOPs QC SOPs Micro SOPs HVAC Production SOPs Stores SOPs Checklists Maintenance SOPs HPLC Sterile GLP Validation Protocols Water System GDP Regulatory Maintenance Calibration Warning Letters Education B.Pharmacy
Resume Pro Video Tutorials
Subscribe on Youtube


Show All ❭❭Jobs by PharmaJobs

Follow Pharmaguideline



Editable Pharmaceutical Documents in MS-Word Format. Ready to use SOPs, Protocols, Master Plans, Manuals and more...




Pharmaceutical Updates

✔ Worldwide Regulatory Updates
✔ Pharmaceutical News Updates
✔ Interview Questions and Answers
✔ All Guidelines in One Place


Recent Posts