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प्रश्न
A violet compound of manganese (A) decomposes on heating to liberate oxygen and compounds (B) and (C) of manganese are formed. Compound (C) reacts with KOH in the presence of potassium nitrate to give compound (B). On heating compound (C) with conc. \[\ce{H2SO4}\] and \[\ce{NaCl}\], chlorine gas is liberated and a compound (D) of manganese along with other products is formed. Identify compounds A to D and also explain the reactions involved.
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उत्तर
The compounds A, B, C and D are given as under:
A = \[\ce{KMnO4}\]
B = \[\ce{K2MnO4}\]
C = \[\ce{MnO2}\]
D = \[\ce{MnCl2}\]
The reactions are explained as under:
\[\ce{\underset{(A)}{KMnO4} ->[Δ] \underset{(B)}{K2MnO4} + \underset{(C)}{MnO2} + O2}\]
\[\ce{MnO2 + KOH + O2 -> 2K2MnO4 + 2H2O}\]
\[\ce{MnO2 + 4NaCl + 4H2SO4 -> \underset{(D)}{MnCl2} + 2NaHSO4 + 2H2O + Cl2}\]
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संबंधित प्रश्न
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Mn3+, Cr3+, V3+ and Ti3+. Which one of these is the most stable in an aqueous solution?
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| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
How would you account for the following?
Transition metals and their compounds act as catalysts.
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Which of the following ions show higher spin only magnetic moment value?
(i) \[\ce{Ti^3+}\]
(ii) \[\ce{Mn2+}\]
(iii) \[\ce{Fe2+}\]
(iv) \[\ce{Co3+}\]
Match the properties given in Column I with the metals given in Column II.
| Column I (Property) | Column II (Metal) | |
| (i) | Element with highest second ionisation enthalpy |
(a) \[\ce{Co}\] |
| (ii) | Element with highest third ionisation enthalpy |
(b) \[\ce{Cr}\] |
| (iii) | \[\ce{M}\] in \[\ce{M(CO)6}\] is | (c) \[\ce{Cu}\] |
| (iv) | Element with highest heat of atomisation |
(d) \[\ce{Zn}\] |
| (e) \[\ce{Ni}\] |
Identify the metal and justify your answer.
\[\ce{MO3F}\]
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In case of transition elements, ions of the same charge in a given series show progressive decrease in radius with increasing atomic number.
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The oxidation state of Fe in [Fe(CO)5] is ______.
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(Atomic number: Mn = 25, Co = 27, Ni = 28)
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Explain the use of different transition metals as catalysts.
