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Questions
Give reasons for the following:
The transition metals generally form coloured compounds.
Explain giving reason:
The transition metals generally form coloured compounds.
Compounds of transition metals are generally coloured. Give reason.
Why the transition metals generally form coloured compounds?
Explain giving reason:
Transition elements usually form coloured ions.
Why are most of the transition metals and their compounds coloured? Explain.
Explain why transition elements usually form coloured ions
Why are the compounds of transition elements coloured?
Examine the following observation:
Transition elements generally form coloured compounds.
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Solution
Most transition metal ions are coloured in solution and solid states. This is due to the partial absorption of visible light. The absorbed light excites the electron from one orbital to another orbital of the same d-subshell. Since the electronic transitions occur in the d-orbitals of metal ions, they are called d-d transitions. These appear coloured due to the d-d transitions that occur in transition metal ions by absorbing visible light.
Notes
Students can refer to the provided solutions based on their preferred marks.
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RELATED QUESTIONS
Complete the following chemical equations:
`(i) Cr_2O_7^(2-)+6Fe^(2+)+14H^+ ->`
`(ii) 2CrO_4^(2-)+2H^+ ->`
`(iii) 2MnO_4^-+5C_2O_4^(2-)+16H^+ ->`
|
`E_((M^(2+)/M)` |
Cr | Mn | Fe | Co | Ni | Cu |
| -0.91 | -1.18 | -0.44 | -0.28 | -0.25 | -0.34 |
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(1) Why is `E_(((Cu^(2+))/(Cu)))` value exceptionally positive
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Electronic configurations
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`Fe^(2+) + MnO_4^(-) + H^+ ->`
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\[\ce{Sn^{2+}_{ (aq)} + 2e^- -> Sn_{(s)}}\]; E0 = −0.14 V
\[\ce{Fe^{3+}_{ (aq)} + e^- -> Fe^{2+}_{ (aq)}}\]; E0 = +0.77 V
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Copper has an exceptionally positive `"E"_("M"^(2+)//"M")^0` value.
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