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प्रश्न
Mention any three processes where transition metals act as catalysts.
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उत्तर
(i) Vanadium (V) oxide in contact process for oxidation of \[\ce{SO2}\] to \[\ce{SO3}\].
(ii) Finely divided iron in Haber’s process in conversion of \[\ce{N2}\] and \[\ce{H2}\] to \[\ce{NH3}\].
(iii) \[\ce{MnO2}\] in preparation of oxygen from \[\ce{KClO3}\].
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संबंधित प्रश्न
Account for the following:
Cu+ ion is unstable in aqueous solution.
The \[\ce{E^{\circ}_{(M^{2+}/M)}}\] value for copper is positive (+0.34 V). What is possible reason for this? (Hint: consider its high ΔaH° and low ΔhydH°)
Give reasons:
E° value for the Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.
Why does the density of transition elements increase from Titanium to Copper? (at. no. Ti = 22, Cu = 29)
Why do transition metals exhibit higher enthalpy of atomization?
Transition elements form binary compounds with halogens. Which of the following elements will form \[\ce{MF3}\] type compounds?
(i) \[\ce{Cr}\]
(ii) \[\ce{Co}\]
(iii) \[\ce{Cu}\]
(iv) \[\ce{Ni}\]
When a brown compound of manganese (A) is treated with \[\ce{HCl}\] it gives a gas (B). The gas taken in excess, reacts with \[\ce{NH3}\] to give an explosive compound (C). Identify compounds A, B and C.
Assertion: \[\ce{Cu^2+}\] iodide is not known.
Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.
When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, a yellow solution of compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C) can be crystallised from the solution. When compound (C) is treated with KCl, orange crystals of compound (D) crystallise out. Identify A to D and also explain the reactions.
Fill in the blanks by choosing the appropriate word(s) from those given in the brackets:
(activation energy, Threshold energy, increased, lowered, partially, full, d-d transition, Benzoic acid, benzaldehyde)
Only those transition metal ions will be coloured which have ______ filled d-orbitals facilitating ______.
A metallic ion 'M' reacts with chloride ion to form white precipitate which is readily soluble in aqueous ammonia. Identify 'M'?
Catalytic hydrogenation of benzene gives
Photographic film and plates have - au essential ingredient of
Agcl is soluble in NH4OH. The solubility is due to the information of:-
The electrode potential of M2+/M of 3d-series elements shows the positive value for ______.
Which property of transition metals enables them to behave as catalysts?
Complete the following reaction and justify that it is a disproportionation reaction:
\[\ce{3MnO^{2-}4 + 4H^+ -> \underline{}\underline{}\underline{}\underline{} + \underline{}\underline{}\underline{}\underline{} + 2H2O}\]
Give a reason for the following:
Transition metals possess a great tendency to form complex compounds.
Why are interstitial compounds well known for transition metals?
