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प्रश्न
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with oxalic acid? Write the ionic equation for the reaction.
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उत्तर
Potassium permanganate can be made by the following methods:
In the laboratory, salts of the manganese (II) ion are oxidized by oxydisulfate to form permanganates.
\[\ce{2Mn^{2+} + 5S2O^{2-}_8 + 8H2O -> 2MnO^-_4 + 10SO^{2-}_4 + 16H^+}\]
The chemical reactions of acidic potassium permanganate are as follows:
\[\begin{array}{cc}
\ce{COO^-}\phantom{.......}\\
\ce{2MnO^-_4 + 16H^+ + 5 | -> 2Mn^{2+} + 8H2O + 10CO2 ^}\\
\ce{COO^-}\phantom{.......}
\end{array}\]
संबंधित प्रश्न
Complete the following equations: Cr2O72- + 14H+ + 6I →
Complete the following equations : 2 MnO2 + 4 KOH + O2 →
Complete the following equations : MnO4- + 4H+ + 3e- →
Describe the preparation of potassium dichromate from iron chromite ore. What is the effect of increasing pH on a solution of potassium dichromate?
Describe the preparation of potassium dichromate from iron chromite ore. What is the effect of increasing pH on a solution of potassium dichromate?
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-.
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) \[\ce{2MnO^{-}4 + 3Mn^{2+} + 2H2O -> 5MnO2 + 4H^{+}}\]
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 \[\ce{Cu^2+}\] ion is treated with \[\ce{KI}\], a white precipitate is formed. Explain the reaction with the help of chemical equation.
The product formed upon heating methyl bromide with potassium tert-butoxide is
KMnO4 is coloured due to ______.
Potassium dichromate when heated with concentrated sulphuric acid and a soluble chloride, gives brown-red vapours of ______.
Complete the reaction mentioning all the products formed:
\[\ce{2KMnO4 ->[\Delta]}\]
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
