(a) What is Lanthanoids contraction ?
(b) What are Interstial compounds ? Give one example
(c) Calculate the spin only magnetic moment of `M^(2+)(aq)` ion [Z=29].

Explanation

(a) N/A
(b) N/A
(c) `M^(2+)(aq)` ion with Z=29 is `Cu^(2+)` ion. Its electronic configuration is `3d^(9) [uarrdarr uarr darr uarrdarruarr darruarr]`. With one unpaired electron, the magnetic moment can be calculated as `=sqrt(n(n+2))=sqrt(3)=1.732 BM`