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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.
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उत्तर
Potassium permanganate can be made by the following methods:
It is produced industrially by the alkaline oxidative fusion of MnO2 followed by the electrolytic oxidation of manganate (VI).
\[\ce{MnO2 ->[Fused with KOH, oxidised with air or KNO3] \underset{manganate ion}{MnO^2-_4}}\]
\[\ce{\underset{manganate}{MnO^2-_4} ->[Electrolytic oxidation in alkaline solution] \underset{permanganate ion}{MnO^-_4}}\]
The chemical reactions of acidic potassium permanganate are as follows:
\[\ce{2MnO^-4 + 2H2O + 5SO2 -> 2Mn^2+ + 4H^+ + 5SO^2-_4}\]
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संबंधित प्रश्न
Complete the following equations:
Complete the following equation:
\[\ce{2MnO4- + 6H+ + 5NO2- ->}\]
When chromite ore FeCr2O4 is fused with NaOH in presence of air, a yellow-coloured compound (A) is obtained, which on acidification with dilute sulphuric acid gives a compound (B). Compound (B) on reaction with KCl forms an orange coloured crystalline compound (C).
(i) Write the formulae of the compounds (A), (B) and C.
(ii) Write one use of compound (C).
Complete the following equations : MnO4- + 4H+ + 3e- →
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.
Give an example and suggest a reason for the following feature of the transition metal chemistry:
A transition metal exhibits the highest oxidation state in oxides and fluorides.
Indicate the steps in the preparation of K2Cr2O7 from chromite ore.
Account for the following :
Manganese shows maximum number of oxidation states in 3d series.
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+ ?
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) \[\ce{2MnO^{-}4 + 3Mn^{2+} + 2H2O -> 5MnO2 + 4H^{+}}\]
Which of the following is amphoteric oxide?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
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.
KMnO4 is coloured due to ______.
Complete the reaction mentioning all the products formed:
\[\ce{Cr2O^{2-}7 + 3H2S + 8H^+ ->}\]
Which of the following ions will have a magnetic moment value of 1.73 BM.
\[\ce{Sc^3+, Ti^3+, Ti^2+, Cu^2+, Zn^2+}\]
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.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
