Q5(f). Which complex has the larger Δₒ
Which complex ion has higher value of crystal field splitting energy (Δₒ)? Justify your answer. (i) [Co(H₂O)₆]³⁺ or [Co(H₂O)₆]²⁺ (ii) [Co(NH₃)₆]³⁺ or [Rh(NH₃)₆]³⁺ (iii) [Co(H₂O)₆]³⁺ or [Co(NH₃)₆]³⁺
Answer in brief
(i) [Co(H₂O)₆]³⁺ (ii) [Rh(NH₃)₆]³⁺ (iii) [Co(NH₃)₆]³⁺.
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Coverscrystal field splitting energyspectrochemical serieshigh spin low spinoctahedral complexescobalt and rhodium complexes
All parts of Question 5
- 5(a) Activation energy from two rate constants5 marks
- 5(b) Light absorbed by a dye solution5 marks
- 5(c) Surface area of charcoal from a nitrogen monolayer5 marks
- 5(d) Showing that a decomposition is first order5 marks
- 5(e) Structure of [4Fe–4S] ferredoxin5 marks
- 5(f) Which complex has the larger Δₒ10 marks
- 5(g) Completing five p-block reactions10 marks
- 5(h) Magnetic moment: spin only in the d-block, not in the f-block5 marks