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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 equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
Complete the following equations : 2 Na2CrO4 + 2 H + →
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 permanganate. How does the acidified permanganate solution react with iron (II) ions? Write the ionic equation for the reaction.
Indicate the steps in the preparation of KMnO4 from pyrolusite ore.
Name a member of the lanthanoid series that is well-known to exhibit +2 oxidation state.
Account for the following :
Manganese shows maximum number of oxidation states in 3d series.
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 is amphoteric oxide?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
Generally transition elements and their salts are coloured due to the presence of unpaired electrons in metal ions. Which of the following compounds are coloured?
(i) \[\ce{KMnO4}\]
(ii) \[\ce{Ce(SO4)2}\]
(iii) \[\ce{TiCl}\]
(iv) \[\ce{Cu2 Cl2}\]
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.
Potassium permanganate on heating at 513 K gives a product which is ______.
Complete the reaction mentioning all the products formed:
\[\ce{Cr2O^{2-}7 + 3H2S + 8H^+ ->}\]
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.
