Advertisements
Advertisements
प्रश्न
How would you account for the following : Transition metals form coloured compounds
Explain The transition metals generally form coloured compounds.
Advertisements
उत्तर १
In the presence of ligands, the d-orbitals of transition metal ions split up into two sets of orbitals having different energies. Thus, the transition of electrons takes place from one set to another. The energy required for these transitions is quite less and falls in the visible region of radiation. The ions of transition metals absorb the radiation of a particular wavelength and the rest is reflected, imparting colour to the solution.
उत्तर २
Most of the complexes of transition metals are coloured. This is because of the absorption of radiation from visible light region to promote an electron from one of the d−orbitals to another. In the presence of ligands, the d-orbitals split up into two sets of orbitals having different energies. Therefore, the transition of electrons can take place from one set toanother. The energy required for these transitions is quite small and falls in the visible region of radiation. The ions of transition metals absorb the radiation of a particular wavelength and the rest is reflected, imparting colour to the solution
APPEARS IN
संबंधित प्रश्न
Which of the following cations are coloured in aqueous solutions and why ?
Sc3+, V3+, Ti4+, Mn2+ (At. Nos. Sc = 21, V = 23, Ti = 22, Mn = 25)
Account for the following:
Cu+2 salts are coloured, while Zn2+ salts are white.
The elements of 3d transition series are given as: Sc Ti V Cr Mn Fe Co
Answer the following: Write the element which shows maximum number of oxidation states. Give reason.
Explain why Cu+ ion is not stable in aqueous solutions?
Comment on the statement that elements of the first transition series possess many properties different from those of heavier transition elements.
Which one of the following ions is coloured?
Give reasons:
E° value for the Mn3+/Mn2+ couple is much more positive than that for Fe3+/Fe2+.
Account for the following :
Ti4+ is colourless whereas V4+ is coloured in an aqueous solutions.
Explain why Mn2+ is more stable than Fe2+ towards oxidation to +3 state. (At. no. of Mn = 25, Fe = 26)
Explain why does colour of KMnO4 disappear when oxalic acid is added to its solution in acidic medium.
A solution of \[\ce{KMnO4}\] on reduction yields either a colourless solution or a brown precipitate or a green solution depending on pH of the solution. What different stages of the reduction do these represent and how are they carried out?
Assertion: The highest oxidation state of osmium is +8.
Reason: Osmium is a 5d-block element.
Identify the metal and justify your answer.
Carbonyl \[\ce{M(CO)5}\]
It has been observed that first ionization energy of 5 d series of transition elements are higher than that of 3d and 4d series, explain why?
Which of the following ions will exhibit colour in aqueous solution?
Why are all copper halides known except that copper iodide?
The oxidation state of Fe in [Fe(CO)5] is ______.
Give a reason for the following:
Transition metals possess a great tendency to form complex compounds.
