reason for anomalous behaviour of Mn and Tc in case of melting point?
Dear student!
The melting point of transition element is high due to stronger metal - metal interaction which increases with increase in no. of unpaired electrons till the middle of the series and after that the no. of unpaired electrons decreases and so metal interaction also decreases due to more repulsion between the electrons.
Now, Mn and Tc are of 3d and 4d transition series which have exceptionally low melting point due to stable d5 configuration where electrons are less delocalised & interaction is comparatively weaker.