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प्रश्न
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
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उत्तर
`"_22 Ti = [Ar]3d 4s^2`
22Ti4+ = [Ar]3d3 4S0 → No electrons for excitation so 4 Ti4+ is colourless.
23V = [Ar]3d3 4s2
V4+ = 3d1 4s0 → 1 electron is there for excitation and it impart blue colour in aquous
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संबंधित प्रश्न
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Read the passage given below and answer the following question:
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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.
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Based on this information, answer the following question:
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