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प्रश्न
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.
\[\ce{MnO2 ->[{Fused with KOH, oxidised with air or KNO3}] \underset{{manganate ion}}{MnO^{2-}_4}}\]
\[\ce{\underset{{manganate ion}}{MnO^{2-}_4} ->[{Electrolytic oxidation in alkaline solution}] \underset{{permanganate ion}}{MnO^-_4}}\]
The chemical reactions of acidic potassium permanganate with SO2 are as follows –
\[\ce{2MnO4 + 2H2O + 5SO2 -> 2Mn^{2+} + 4H^+ + 5SO^{2-}_4}\]
उत्तर २
\[\ce{2MnO2 + 4KOH + O2 ->[\Delta] 2K2MnO4 + 2H2O}\]
\[\ce{3MnO^2-_4 + 4H+ -> 2MnO^-_4 + MnO2 + 2H2O}\]
Notes
Students can refer to the provided solutions based on their preferred marks.
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संबंधित प्रश्न
Complete the following equations : 2 MnO2 + 4 KOH + O2 →
Complete the following equations : 2 Na2CrO4 + 2 H + →
Name the oxometal anions of the first series of the transition metals in which the metal exhibits the oxidation state equal to its group number.
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with iron (II) ions? Write the ionic equation for the reaction.
Give an example and suggest a reason for the following feature of the transition metal chemistry:
The highest oxidation state is exhibited in oxoanions of a metal.
Complete the following equation :
Complete the following chemical equations :
Cu + H2SO4(conc.) →
Name a member of the lanthanoid series that is well-known to exhibit +2 oxidation state.
E0 value for Mn3+ Mn2+ couple is much more positive than that for Cr3-/ Cr2-.
On addition of small amount of \[\ce{KMnO4}\] to concentrated \[\ce{H2SO4}\], a green oily compound is obtained which is highly explosive in nature. Identify the compound from the following.
\[\ce{KMnO4}\] acts as an oxidising agent in alkaline medium. When alkaline \[\ce{KMnO4}\] is treated with \[\ce{KI}\], iodide ion is oxidised to ______.
In the form of dichromate, \[\ce{Cr (VI)}\] is a strong oxidising agent in acidic medium but \[\ce{Mo (VI)}\] in \[\ce{MoO3}\] \[\ce{and W (VI)}\] in \[\ce{WO3}\] are not because:
(i) \[\ce{Cr(VI)}\] is more stable than \[\ce{Mo(VI)}\] and \[\ce{and W(VI)}\].
(ii) \[\ce{Mo(VI)}\] and \[\ce{and W(VI)}\] are more stable than \[\ce{Cr(VI)}\].
(iii) Higher oxidation states of heavier members of group-6 of transition series are more stable.
(iv) Lower oxidation states of heavier members of group-6 of transition series are more stable.
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?
Potassium permanganate on heating at 513 K gives a product which is ______.
Indicate the step in the preparation of K2Cr2O7 from chromite ore.
Indicate the steps in the preparation of 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.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with oxalic acid? Write the ionic equation for the reaction.
