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प्रश्न
In 3d series (Sc to Zn), which element has the lowest enthalpy of atomisation and why?
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उत्तर
In the 3d series, from Sc to Zn, only zinc has filled valence shells. The valence shell electronic configuration of Zn is 3d104s2. Due to the absence of unpaired electrons in ns and (n–1)d shells, the interatomic electronic bonding is the weakest in zinc. Consequently, zinc has the least enthalpy of atomisation in the 3d series of transition elements.
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