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प्रश्न
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.
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उत्तर
The highest oxidation states of transition metals are observed in oxides and fluorides. Because oxygen and fluorine are highly electronegative elements and small in size, they are strong oxidising agents. For example, chromium displays a +6 oxidation state in CrF6, and vanadium displays a +5 oxidation state in V2O5.
संबंधित प्रश्न
Complete the following equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
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 K2Cr2O7 from chromite ore.
Complete the following equations:
`2MnO_4^(-)+16H^++5S^(2-)rarr`
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-.
Using IUPAC norms, write the formula of potassium trioxalatochromate(III).
Zinc carbonate is precipitated from zinc sulphate solution by the addition of ___________.
Which of the following is amphoteric oxide?
\[\ce{Mn2O7, CrO3, Cr2O3, CrO, V2O5, V2O4}\]
\[\ce{KMnO4}\] acts as an oxidising agent in alkaline medium. When alkaline \[\ce{KMnO4}\] is treated with \[\ce{KI}\], iodide ion is oxidised to ______.
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.
Why \[\ce{HCl}\] should not be used for potassium permanganate titrations?
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 \[\ce{K2Cr2O2}\] 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.
Indicate the steps in the preparation of \[\ce{K2Cr2O7}\] from chromite ore.
