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प्रश्न
Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.
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उत्तर १
- In the first transition series, lower oxidation states are more stable, while heavier transition elements have higher oxidation states.
- The 5d transition series exhibits higher ionization enthalpy compared to the 3d and 4d transition series.
- M-M bonding is prevalent in heavier transition metals, but less so in the first series.
- The elements in the first transition series do not form complexes with coordination numbers of 7 or 8.
- Elements in the first series can form high or low-spin complexes based on ligand strength, while those in the other series form low-spin complexes regardless of ligand strength.
उत्तर २
This statement is true. According to the heavier transition elements (elements of the second and third transition series), the elements of the first transition series have different atomic radii, melting and boiling temperatures, ionization enthalpies, atomization enthalpies, and other characteristics. Their mentioned characteristics have significantly lower values.
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संबंधित प्रश्न
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
Answer the following: Which element shows only +3 oxidation state?
Which of the 3d series of the transition metals exhibits the largest number of oxidation states and why?
Calculate the ‘spin only’ magnetic moment of \[\ce{M^{2+}_{ (aq)}}\] ion (Z = 27).
What can be inferred from the magnetic moment value of the following complex species?
| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
How would you account for the following?
Transition metals and their compounds act as catalysts.
Give reasons: Sc3+ is colourless in aqueous solution whereas Ti3+ is coloured.
The transition metals show _________ character because of the presence of unpaired· electrons and Cu+ is ____________ because of its electronic configuration is [Ar]3d10
Why do transition metals exhibit higher enthalpy of atomization?
Interstitial compounds are formed when small atoms are trapped inside the crystal lattice of metals. Which of the following is not the characteristic property of interstitial compounds?
Transition elements show magnetic moment due to spin and orbital motion of electrons. Which of the following metallic ions have almost same spin only magnetic moment?
(i) \[\ce{Co^{2+}}\]
(ii) \[\ce{Cr^{2+}}\]
(iii) \[\ce{Mn^{2+}}\]
(iv) \[\ce{Cr^{3+}}\]
Out of \[\ce{Cu2Cl2}\] and \[\ce{CuCl2}\], which is more stable and why?
Assertion: \[\ce{Cu^2+}\] iodide is not known.
Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.
Answer the following question:
Which element of the first transition series has highest second ionisation enthalpy?
Mention any three processes where transition metals act as catalysts.
If enthalpies of formation of C2H4(g), CO2(g) and H2O(l) at 25°C and 1 atm pressure are 52, – 394 and – 286 kJ/mol respectively, the change in ethalpy for combustion of C2H4 is equal to
Which of the following statements is not correct?
The given graph shows the trends in melting points of transition metals:
Explain the reason why Cr has the highest melting point and manganese (Mn) has a lower melting point.
Explain the use of different transition metals as catalysts.
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Atomic sizes
