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प्रश्न
The compounds of \[\ce{Ti^4+}\] ions are colourless due to ______.
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उत्तर
The electronics configuration of
\[\ce{Ti = [Ar]}\]3d24s2 and
\[\ce{Ti^4+ = [Ar]}\]3d0
Due to the absence of unpaired electrons in 3d subshell, d-d transition is not possible. Therefore, \[\ce{Ti^4+}\] ions do not adsorb the radiation in the visible region. Hence, compounds of \[\ce{Ti^4+}\] ions are colourless.
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संबंधित प्रश्न
ln which pair highest oxidation states of transition metals are found:
Calculate magnetic moment of `Fe_((aq))^(2+) ion (Z=26).`
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Answer the following: Which element shows only +3 oxidation state?
Explain why Cu+ ion is not stable in aqueous solutions?
How would you account for the following:
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| Example | Magnetic Moment (BM) |
| K2[MnCl4] | 5.9 |
How would you account for the following?
Zr (Z = 40) and Hf (Z = 72) have almost identical radii.
Complete and balance the following chemical equations
`Fe^(2+) + MnO_4^(-) + H^+ ->`
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)
Read the passage given below and answer the following question:
The transition metals when exposed to oxygen at low and intermediate temperatures form thin, protective oxide films of up to some thousands of Angstroms in thickness. Transition metal oxides lie between the extremes of ionic and covalent binary compounds formed by elements from the left or right side of the periodic table. They range from metallic to semiconducting and deviate by both large and small degrees from stoichiometry. Since electron bonding levels are involved, the cations exist in various valence states and hence give rise to a large number of oxides. The crystal structures are often classified by considering a cubic or hexagonal close-packed lattice of one set of ions with the other set of ions filling the octahedral or tetrahedral interstices. The actual oxide structures, however, generally show departures from such regular arrays due in part to distortions caused by packing of ions of different size and to ligand field effects. These distortions depend not only on the number of d-electrons but also on the valence and the position of the transition metal in a period or group.
In the following questions, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices on the basis of the above passage.
Assertion: Crystal structure of oxides of transition metals often show defects.
Reason: Ligand field effect cause distortions in crystal structures.
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Which element of the first transition series has highest second ionisation enthalpy?
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\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\], E0 = +0.77 V
\[\ce{MnO^{-4}_{ (aq)} + 8H^+ + 5e^- -> Mn^{2+}_{ (aq)} + 4H2O_{(l)}}\], E0 = +1.51 V
What is the cell potential for the redox reaction?
Consider the following standard electrode potential values:
\[\ce{Sn^{2+}_{ (aq)} + 2e^- -> Sn_{(s)}}\]; E0 = −0.14 V
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Eu2+ with electronic configuration [Xe]4f76s2 is a strong reducing agent.
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Based on this information, answer the following question:
- Deduce the structural formula of the complex compound.
- Write the IUPAC name of the complex compound.
- Draw the geometrical isomers of the complex compound.
Match List-I with List-II.
| List-I | List-II |
| A. Haber process | I. Fe catalyst |
| B. Wacker oxidation | II. PdCl2 |
| C. Wilkinson catalyst | III. [(PPh3)3RhCl] |
| D. Ziegler catalyst | IV. TiCl4 with Al(CH3)3 |
Choose the correct answer from the options given below:
