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प्रश्न
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with SO2? Write the ionic equation for the reaction.
Indicate the steps in the preparation of KMnO4 from pyrolusite ore.
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उत्तर १
Potassium permanganate can be made by the following methods –
It is produced industrially by the electrolytic oxidation of manganate (VI), followed by the alkaline oxidative fusion of MnO2.
\[\ce{MnO2 ->[Fused with KOH, oxidised with air or KNO3] \underset{manganate ion}{MnO^2-_4}}\]
\[\ce{\underset{manganate}{MnO^2-_4} ->[Electrolytic oxidation in alkaline solution] \underset{permanganate ion}{MnO^-_4}}\]
The chemical reactions of acidic potassium permanganate are as follows –
\[\ce{2MnO^-4 + 2H2O + 5SO2 -> 2Mn^2+ + 4H^+ + 5SO^2-_4}\]
उत्तर २
\[\ce{2MnO2 + 4KOH + O2 ->[\Delta] 2K2MnO4 + 2H2O}\]
\[\ce{3MnO^2-_4 + 4H+ -> 2MnO^-_4 + MnO2 + 2H2O}\]
संबंधित प्रश्न
Complete the following equations:
Complete the following equations: Cr2O72- + 14H+ + 6I →
Complete the following equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
Complete the following equations : MnO4- + 4H+ + 3e- →
Complete the following chemical equation
Cr2O72- + 3Sn2+ + 14H+ →
Give an example and suggest a reason for the following feature of the transition metal chemistry:
The lowest oxide of transition metal is basic, the highest is amphoteric/acidic.
Write the formula of an oxo-anion of Manganese (Mn) in which it shows the oxidation state equal to its group number.
Name a member of the lanthanoid series that is well-known to exhibit +2 oxidation state.
Write the chemical equation for the preparation of 4 KMnO from 2. MnO Why does purple colour of acidified permanganate solution decolourise when it oxidises Fe2- to Fe3+ ?
Answer the following question.
When MnO2 is fused with KOH in the presence of KNO3 as an oxidizing agent, it gives a dark green compound (A). Compound (A) disproportionates in an acidic solution to give a purple compound (B). An alkaline solution of compound (B) oxidizes KI to compound (C) whereas an acidified solution of compound (B) oxidizes KI to (D). Identify (A), (B), (C), and (D).
Zinc carbonate is precipitated from zinc sulphate solution by the addition of ___________.
Which of the following is amphoteric oxide?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
The oxidation state of manganese in the product obtained in a reaction of potassium permanganate and hydrogen peroxide in a basic medium is ______.
Potassium dichromate when heated with concentrated sulphuric acid and a soluble chloride, gives brown-red vapours of ______.
In the two tetrahedral structures of dichromate ion, ______.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chomite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
