The determination of purity or Assay of Hydrogen Peroxide by a titration method, known as purity of hydrogen peroxide use 2(N) sulfuric acid (H2SO4) solution and 1(N) potassium permanganate (KMnO4) solution.
The chemical formula of hydrogen peroxide is H2O2. It is a light blue-colored liquid that is highly reactive and is used as both an oxidizing agent and a reducing agent in various chemical reactions.
APPARATUS
a). 5 ml stoppered weighing bottle.
b). 500 ml conical flask.
c). 100 ml measuring cylinder.
d). Burette.
REAGENTS
a). Approx. 2(N) sulfuric acid (H2SO4) solution.
b). Standard 1(N) potassium permanganate (KMnO4) solution.
H2O2 Purity Testing Procedure
Measure and transfer 20ml 2N Sulfuric acid solution into a 500ml conical flask. Add 1(N) KMnO4 solution dropwise and shake till a pink color appears and persists.
Take a hydrogen peroxide sample in a 5-ml weighing bottle. From this carefully transfer about 1 gm (accurately weighed) sample into the 500-ml conical flask. Add about 50 ml of distilled water and shake well.
Titrate the content of the conical flask with standard 1(N) KMnO4 solution taken in a burette to the appearance of the same permanent pink color.
\[Assay (%) = (titre, value * normality, KMnO_4 * 1.7008) / (weight, H_2O_2)\]
H2O2 Molar Mass
The molar mass of hydrogen peroxide (H2O2) is 34.01 grams per mole.
To calculate the molar mass of H2O2, we add the atomic masses of each element in the molecule.
Hydrogen (H): 2 atoms x 1.01 g/mol = 2.02 g/mol Oxygen (O): 2 atoms x 15.99 g/mol = 31.98 g/mol
Total molar mass of H2O2 = 2.02 g/mol + 31.98 g/mol = 34.01 g/mol.