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प्रश्न
Name the oxometal anions of the first series of the transition metals in which the metal exhibits the oxidation state equal to its group number.
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उत्तर
In \[\ce{Cr2O^{2-}_7}\] and \[\ce{CrO^{2-}_4}\], chromium shows the +6 state, which is equal to its group number (6).
In \[\ce{MnO^-_4}\], it shows \[\ce{Mn^+_7}\] state, which is equal to its group number (7).
In \[\ce{VO^-_3}\], it shows \[\ce{V^+_5}\] state, which is equal to its group number (5).
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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 equation :
`2MnO_4^(-)+6H^++5NO_2^(-)rarr`
Complete the following equations : 2 Na2CrO4 + 2 H + →
Complete the following chemical equation
Cr2O72- + 3Sn2+ + 14H+ →
Describe the preparation of potassium dichromate from iron chromite ore. What is the effect of increasing pH on a solution of potassium dichromate?
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:
The highest oxidation state is exhibited in oxoanions of a metal.
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+ ?
Using IUPAC norms, write the formula of potassium trioxalatochromate(III).
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) \[\ce{2MnO^{-}4 + 3Mn^{2+} + 2H2O -> 5MnO2 + 4H^{+}}\]
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) \[\ce{Cu2 Cl2}\]
What is the effect of pH on dichromate ion solution?
Complete the following ionic equation:
\[\ce{Cr2O^{2-}7 + 2OH^- ->}\]
Complete the reaction mentioning all the products formed:
\[\ce{2KMnO4 ->[\Delta]}\]
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.
