Describe giving reason which one of the following pairs has the proper – InterviewSolution

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1.	Describe giving reason which one of the following pairs has the property indicated ? (i) Fe or Cu has higher melting point. (ii) `Co^92+)` and `Ni^(2+)` has lowe magnetic moment.
Answer» (i) Fe has higher melting point than Cu. This is because Fe has four unpaired electrons in 3d -subshell while Cu has only one electron in the 4s-subshell. Hence, metallic bonds in Fe are much stronger than those in CU. (ii) `._(27) Co = [Ar] 3d^(7) 4s^(2) ,Co^(2+)= [ Ar] 3d^(7) ( 3 ` unpaired electron) `. _(28) (Ni) =[Ar] 3d^(8) 4s^(2) , Ni^(2+) = [Ar] 3d^(8) ( 2` unpaired electrons) Hence, Ni has lower magnetic moment than Co.

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