Advertisements
Advertisements
Question
How would you account for the following:
Of the d4 species, Cr2+ is strongly reducing while manganese (III) is strongly oxidising.
Solution
Both Cr2+ and Mn3+ have d4 electronic configurations, but their contrasting behaviors arise from the stability of their resulting oxidation states. Cr2+ is strongly reducing because it tends to lose one electron to form Cr3+ (d3 configuration). The d3 configuration has a half-filled t2g subshell in an octahedral field, which is particularly stable due to symmetric electron distribution and lower energy. On the other hand, Mn3+ is strongly oxidizing because it tends to gain one electron to form Mn2+ (d5 configuration). The d5 configuration corresponds to a half-filled d-subshell, which is highly stable due to exchange energy and symmetry. Thus, Cr2+ undergoes oxidation to achieve greater stability, while Mn3+ undergoes reduction for the same reason.
APPEARS IN
RELATED QUESTIONS
Explain why is Fe3+ more stable than Fe2+?
Calculate magnetic moment of `Fe_((aq))^(2+) ion (Z=26).`
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
Answer the following: Which element has the highest m.p?
How would you account for the following: Transition metals form complex compounds.
How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements?
How is the variability in oxidation states of transition metals different from that of the non-transition metals? Illustrate with examples.
What can be inferred from the magnetic moment value of the following complex species?
| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
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?
Which of the following statements is not correct?
Assertion: \[\ce{Cu^2+}\] iodide is not known.
Reason: \[\ce{Cu^2+}\] oxidises \[\ce{I^-}\] to iodine.
Account for the following:
In case of transition elements, ions of the same charge in a given series show progressive decrease in radius with increasing atomic number.
Which of the following species has maximum magnetic momentum?
Which of the following transition metal is not coloured?
Match List - I with List - II.
| List - I | List - II | ||
| (a) | \[\ce{[Fe(CN)6]^3-}\] | (i) | 5.92 BM |
| (b) | \[\ce{[Fe(H2O)6]^3+}\] | (ii) | 0 BM |
| (c) | \[\ce{[Fe(CN)6]^4-}\] | (iii) | 4.90 BM |
| (d) | \[\ce{[Fe(H2O)6]^2+}\] | (iv) | 1.73 BM |
Choose the correct answer from the options given below.
Why are all copper halides known except that copper iodide?
The oxidation state of Fe in [Fe(CO)5] is ______.
Consider the following standard electrode potential values:
\[\ce{Sn^{2+}_{ (aq)} + 2e^- -> Sn_{(s)}}\]; E0 = −0.14 V
\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\]; E0 = +0.77 V
What is the cell reaction and potential for the spontaneous reaction that occurs?
Give a reason for the following:
Transition metals possess a great tendency to form complex compounds.
Describe the oxidising action of potassium dichromate and write the ionic equation for its reaction with H2S.
