February 19, 2025

Preparation and standardization molar and normal solutions of Potassium permanganate

Preparation and standardization molar and normal solutions of Potassium permanganate

Potassium permanganate (KMnO4) is a commonly used chemical in analytical chemistry, and it is often prepared in molar or normal solutions for various analytical purposes. Here is a general procedure for preparing and standardizing molar and normal solutions of potassium permanganate:

  1. Preparation of Molar Solution:
  • Calculate the required mass of KMnO4 to prepare the desired molar solution based on the molecular weight of KMnO4 (158.03 g/mol). For example, to prepare a 0.1 M solution of KMnO4, dissolve 1.5803 g of KMnO4 in 1 L of distilled water.
  • Dissolve the calculated amount of KMnO4 in a small volume of distilled water in a clean, dry 1 L volumetric flask.
  • Add distilled water to the flask until the volume reaches 1 L, and mix thoroughly to ensure uniform distribution of the solute.
  • The resulting solution is a 1 M solution of KMnO4.
  1. Preparation of Normal Solution:
  • Calculate the required mass of KMnO4 to prepare the desired normal solution based on the molecular weight of KMnO4 (158.03 g/mol) and the equivalent weight of KMnO4 (31.61 g/equivalent). For example, to prepare a 0.1 N solution of KMnO4, dissolve 0.3161 g of KMnO4 in 1 L of distilled water.
  • Dissolve the calculated amount of KMnO4 in a small volume of distilled water in a clean, dry 1 L volumetric flask.
  • Add distilled water to the flask until the volume reaches 1 L, and mix thoroughly to ensure uniform distribution of the solute.
  • The resulting solution is a 0.1 N solution of KMnO4.
  1. Standardization:
  • Weigh accurately about 0.2 g of sodium oxalate (Na2C2O4) in a clean and dry weighing boat.
  • Dissolve the weighed sodium oxalate in a small volume of distilled water in a clean and dry 250 mL Erlenmeyer flask.
  • Add 25 mL of dilute sulfuric acid (1:1) to the flask.
  • Titrate the solution with the prepared molar or normal solution of KMnO4 until the pink color persists for at least 30 seconds. Note the volume of KMnO4 solution used.
  • Repeat the titration two more times to obtain consistent values.
  • Calculate the concentration of KMnO4 solution using the following formula:

Molarity of KMnO4 solution = (Weight of sodium oxalate x 2 x Normality of KMnO4) / (Volume of KMnO4 solution x Molecular weight of sodium oxalate)

The standardization process should be repeated periodically to ensure the accuracy of the prepared solution.

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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