Fri February 15, 2013 By: Renu Mariam John

Mn shows a dip in the melting point vs atomic number curve.why?

Expert Reply
Sun February 17, 2013
The elements of first transition series show decreasing tendency to form divalent cationas we move left to right in the series. This trend is due to general increase in the first and secondionization energy.
Mn= 4s2 3d5, Mn is stable in Mn2+ configuration.
The greater stability of Mn2+ is due to half filled d5 configuration. Due to half filled configuration, Mn shows a dip in melting point. 
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