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प्रश्न
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with iron (II) ions? Write the ionic equation for the reaction.
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उत्तर
Potassium permanganate is prepared by fusion of MnO2 with an alkali metal hydroxide and an oxidising agent like KNO3. This produces the dark green K2MnO4, which disproportionates in a neutral or acidic solution to give permanganate.
\[\ce{2MnO2 + 4KOH + O2 -> 2K2MnO4 + 2H2O}\]
\[\ce{3MnO^{2-}_4 + 4H^+ -> 2MnO^-_4 + MnO2 + 2H2O}\]
The chemical reactions of acidic potassium permanganate are as follows:
\[\ce{MnO^-_4 + 8H^+ + 5Fe^2+ -> Mn^2+ + 4H2O + 5Fe^3+}\]
संबंधित प्रश्न
Complete the following equations:
Complete the following equations : 2 MnO2 + 4 KOH + O2 →
Complete the following equations : 2 Na2CrO4 + 2 H + →
Complete the following equations:Cr2O72- + 2OH- →
Indicate the steps in the preparation of K2Cr2O7 from chromite ore.
Complete the following equation :
E0 value for Mn3+ Mn2+ couple is much more positive than that for Cr3-/ Cr2-.
Zinc carbonate is precipitated from zinc sulphate solution by the addition of ___________.
Which of the following reactions are disproportionation reactions?
(a) \[\ce{Cu^{+} -> Cu^{2+} + Cu}\]
(b) \[\ce{3MnO^{-}4 + 4H^{+} -> 2MnO^{-}4 + MnO2 + 2H2O}\]
(c) \[\ce{2KMnO4 -> K2MnO4 + MnO2 + O2}\]
(d) \[\ce{2MnO^{-}4 + 3Mn^{2+} + 2H2O -> 5MnO2 + 4H^{+}}\]
When orange solution containing \[\ce{Cr2O^{2-}7}\] ion is treated with an alkali, a yellow solution is formed and when \[\ce{H^+}\] ions are added to yellow solution, an orange solution is obtained. Explain why does this happen?
The product formed upon heating methyl bromide with potassium tert-butoxide is
KMnO4 is coloured due to ______.
The oxidation state of manganese in the product obtained in a reaction of potassium permanganate and hydrogen peroxide in a basic medium is ______.
In the two tetrahedral structures of dichromate ion, ______.
Complete the reaction mentioning all the products formed:
\[\ce{Cr2O^{2-}7 + 3H2S + 8H^+ ->}\]
Indicate the steps in the preparation of \[\ce{K2Cr2O2}\] from chromite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
