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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.
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
Complete the following equation:
\[\ce{2MnO4- + 6H+ + 5NO2- ->}\]
Complete the following chemical equation
8MnO4- + 3S2O32- + H2O →
Complete the following equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
Complete the following equations:Cr2O72- + 2OH- →
Complete the following chemical equation
Cr2O72- + 3Sn2+ + 14H+ →
Give an example and suggest a reason for the following feature of the transition metal chemistry:
The lowest oxide of transition metal is basic, the highest is amphoteric/acidic.
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.
Account for the following :
Manganese shows maximum number of oxidation states in 3d series.
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?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
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.
The product formed upon heating methyl bromide with potassium tert-butoxide is
Why \[\ce{HCl}\] should not be used for potassium permanganate titrations?
What is the effect of pH on dichromate ion solution?
Complete the reaction mentioning all the products formed:
\[\ce{2KMnO4 ->[\Delta]}\]
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 step in the preparation of K2Cr2O7 from chromite ore.
Describe the preparation of potassium permanganate. How does the acidified permanganate solution react with SO2? Write the ionic equation for the reaction.
