Advertisements
Advertisements
प्रश्न
An aqueous pink solution of cobalt (II) chloride changes to deep blue on addition of excess of HCl. This is because:
(i) \[\ce{[Co(H2O)6]^{2+}}\] is transformed into \[\ce{[CoCl6]}^{4-}\]
(ii) \[\ce{[Co(H2O)6]^{2+}}\] is transformed into \[\ce{[CoCl4]}^{2-}\]
(iii) tetrahedral complexes have smaller crystal field splitting than octahedral complexes.
(iv) tetrahedral complexes have larger crystal field splitting than octahedral complex.
उत्तर
(ii) \[\ce{[Co(H2O)6]^{2+}}\] is transformed into \[\ce{[CoCl4]}^{2-}\]
(iii) tetrahedral complexes have smaller crystal field splitting than octahedral complexes.
Explanation:
Aqueous pink solution of cobalt (II) chloride is due to electronic transition of electron from t2g to eg energy level of \[\ce{[Co(H2O)6]^{2+}}\] complex. When excess of HCl is added to this solution
(i) \[\ce{[Co(H2O)6]^{2+}}\] is transformed into \[\ce{[CoCl4]^{2-}}\].
(ii) Tetrahedral complexes have smaller crystal field splitting than octahedral complexes because Δr = `4/9` Δ0
APPEARS IN
संबंधित प्रश्न
The hexaquo manganese (II) ion contains five unpaired electrons, while the hexacyanoion contains only one unpaired electron. Explain using Crystal Field Theory.
Draw figure to show the splitting of d orbitals in an octahedral crystal field.
Why are low spin tetrahedral complexes rarely observed?
Atomic number of \[\ce{Mn, Fe, Co}\] and Ni are 25, 26, 27 and 28 respectively. Which of the following outer orbital octahedral complexes have same number of unpaired electrons?
(i) \[\ce{[MnCl6]^{3-}}\]
(ii) \[\ce{[FeF6]^{3-}}\]
(iii) \[\ce{[CoF6]^{3-}}\]
(iv) \[\ce{[Ni(NH3)6]^{2+}}\]
[Ni(H2O)6]2+ (aq) is green in colour whereas [Ni(H2O)4 (en)]2+ (aq)is blue in colour, give reason in support of your answer.
What is crystal field splitting energy?
For octahedral Mn(II) and tetrahedral Ni(II) complexes, consider the following statements:
(i) Both the complexes can be high spin.
(ii) Ni(II) complex can very rarely below spin.
(iii) With strong field Ligands, Mn(II) complexes can be low spin.
(iv) Aqueous solution of Mn (II) ions is yellow in colour.
The correct statements are:
Consider that d6 metal ion (M2+) forms a complex with aqua ligands and the spin only magnetic moment of the complex is 4.90 BM. The geometry and the crystal field stabilization energy of the complex is:
On the basis of crystal field theory, write the electronic configuration for the d5 ion with a weak ligand for which Δ0 < P.
On the basis of crystal field theory, write the electronic configuration for d4 with a strong field ligand for which Δ0 > P.
