Q7(e). Magnetic behaviour of copper(II) acetate and [Cu(CN)₄]³⁻
Compare and comment on the magnetic properties of the following complexes: (i) [Cu(OAc)₂]₂ (ii) [Cu(CN)₄]³⁻
Answer in brief
(i) A dimer of two Cu(II), d⁹, ions whose spins are coupled antiparallel: μ ≈ 1.4 BM per Cu at room temperature, falling towards zero on cooling. (ii) Cu(I), d¹⁰: diamagnetic at all temperatures.
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Coverscopper(II) acetate dimerantiferromagnetic couplingsubnormal magnetic momentsuperexchangediamagnetic complexspin-only moment
All parts of Question 7
- 7(a) An optically active square-planar complex10 marks
- 7(b) Aqueous LaCl₃ and LuCl₃: which is more acidic10 marks
- 7(c) Opposing first-order reactions: time to form half the equilibrium amount10 marks
- 7(d) Surface area of an adsorbent from the nitrogen monolayer10 marks
- 7(e) Magnetic behaviour of copper(II) acetate and [Cu(CN)₄]³⁻10 marks