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Why HCl is not used in the standardization of KMnO4 experiment?

Why HCl is not used in the standardization of KMnO4 experiment?

Hydrochloric acid (HCl) is usually not used in the process of titration because it reacts with the indicator potassium permanganate (KMnO4) that is used in the process. It reacts with KMnO4 solution and gets oxidized which further results in the liberation of chlorine gas.

Does KMnO4 react with HCl?

Potassium permanganate is a powerful oxidizing agent and it does not react with Conc. HCl at high temperatures. Hydrochloric acid is a mild reducing agent and is oxidised to free chlorine, when it is heated with the potassium permanganate.

How do you prepare and standardize 0.1 N potassium permanganate?

Preparation of 0.1 N Potassium Permanganate Solution

  1. Dissolve 3.2 g of Potassium Permanganate (KMnO4) in 100 mL of water and dilute the solution with water to 1 L.
  2. Allow the solution to stand in the dark for two weeks and then filter through a fine-porosity sintered-glass crucible. Do not wash the filter.

Why h2so4 is used for acidification of KMnO4 solution and not HCl?

The acid used in this titration is dilute sulphuric acid. Nitric acid is not used as it is itself an oxidising agent and hydrochloric acid is usually avoided because it reacts with KMnO4 according to the equation given below to produce chlorine and chlorine which is also an oxidising agent in the aqueous solution.

Why is h2so4 used to acidify KMnO4?

Titrations with Permanganate must be carried out in strong acid solution. Sulfuric Acid is generally used for this purpose because Nitric Acid and Hydrochloric Acid can participate in competing oxidation-reduction reactions, reducing the accuracy of the titration.

Why can HCl be used to acidify KMnO4?

KMnO4 is strong oxidizing agent and it oxidize HCl. Permanganate will react with hydrochloric acid to liberate chlorine. Hence HCl is not used to acidify a permanganate solution in volumetrically. What is lanthanoid contraction?

What happens when KMnO4 reacts with conc HCl?

KMnO4 reacts vigorously with hydrochloric acid to generate toxic chlorine gas.

How will you prepare and standardize 250 mL of 0.1 N potassium permanganate?

Add 250 mL of purified water (freshly boiled and cooled) and 10 mL sulfuric acid (96% H2SO4, sp g 1.84). Add rapidly from a buret about 95% of the theoretical quantity of potassium permanganate solution needed; stir until the solution is clear.

Why the KMnO4 solution must be standardized before use?

Some chemical reactions are very sensitive to the exact amount of reagents used otherwise the reaction will not work properly. Once the exact concentration has been determined, the solution is said to be standardized and you can then add exact amounts of the KMnO4 to a chemical reaction.