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प्रश्न
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.
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उत्तर
Metal oxoanions show higher oxidation states, for example, in \[\ce{Cr2O^{2-}_7}\] the oxidation state of Cr is +6, while in \[\ce{MnO^-_4}\] the oxidation state of Mn is +7. The reason for the combination of metal with oxygen is that oxygen is a highly electronegative and oxidizing element.
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संबंधित प्रश्न
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 : 2 MnO2 + 4 KOH + O2 →
Write the formula of an oxo-anion of Manganese (Mn) in which it shows the oxidation state equal to its group number.
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.
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+ ?
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?
Potassium permanganate acts as an oxidant in neutral, alkaline as well as acidic media. The final products obtained from it in the three conditions are, respectively.
What is the effect of pH on dichromate ion solution?
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:
\[\ce{2KMnO4 ->[\Delta]}\]
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.
