May 19, 2024

Conductometric titration of strong acid against a strong base

Conductometric titration of strong acid against a strong base


To Determine Normality of given acid by conductometry


Hydrochloric acid is a strong acid and sodium hydroxide is a strong base. The strength of HCL can be determined by titrating it directly with sodium hydroxide. The conductance first falls due to the replacement of the hydrogen ion (Δ350) by the added cation (Δ 40-80) and then after the equivalence point has been reached, rapidly rises with further addition of strong alkali due to the large values of the hydroxyl ion (198). The two branches of the curve are straight lines provided the volume of the reagent added is negligible and their intersection gives the endpoint (curves 1 and 2)


For Strong acid content determination

  1. Wash and dry all glasswares as per standard laboratory procedure.
  2. Rinse all glasswares with distilled water.
  3. Rinse the burette with small portion of NaOH solution and fill the burette with standard NaOH solution.
  4. Add 50 ml of hydrochloric acid or unknown sample of given strong acid in a beaker.
  5. Immerse the platinum electrodes in this solution (add some distilled water if sample amount is small).
  6. Note the initial conductance of sample before starting titration.
  7. Add       ml NaOH at a time from burette and note down the change in conductance after each ml.
  8. Continue until the conductance value after falling once starts increasing (end point).
  9. Plot the graph between conductance vs. volume of NaOH added.
  10. The point of intersection between two curves indicates the end point titration.


Indian Pharmacopoeia 2007, Volume 1, Pg no 115.

First Year B Pharm Notes, Syllabus, Books, PDF Subjectwise/Topicwise

F Y B Pharm Sem-IF Y B Pharm Sem-II
BP101T Human Anatomy and Physiology I TheoryBP201T Human Anatomy and Physiology II – Theory
BP102T Pharmaceutical Analysis I TheoryBP202T Pharmaceutical Organic Chemistry I Theory
BP103T Pharmaceutics I TheoryBP203T Biochemistry – Theory
BP104T Pharmaceutical Inorganic Chemistry TheoryBP204T Pathophysiology – Theory
BP105T Communication skills TheoryBP205T Computer Applications in Pharmacy Theory
BP106RBT Remedial BiologyBP206T Environmental sciences – Theory
BP106RMT Remedial Mathematics TheoryBP207P Human Anatomy and Physiology II Practical
BP107P Human Anatomy and Physiology PracticalBP208P Pharmaceutical Organic Chemistry I Practical
BP108P Pharmaceutical Analysis I PracticalBP209P Biochemistry Practical
BP109P Pharmaceutics I PracticalBP210P Computer Applications in Pharmacy Practical
BP110P Pharmaceutical Inorganic Chemistry Practical
BP111P Communication skills Practical
BP112RBP Remedial Biology Practical

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