Question

Which element has the least energy of atomisation in d-block & why

Answer 1

Sc & zn belongs to 3rd group pf periodic table. The extent of metallic bonding an element undergoes decides the enthalpy of atomization. The more extensive the metallic bonding of an element, the more will be its enthalpy of atomization. In all transition metals (except Zn, electronic configuration: 3d10 4s2), there are some unpaired electrons that account for their stronger metallic bonding. Due to the absence of these unpaired electrons, the inter-atomic electronic bonding is the weakest in Zn and as a result, it has the least enthalpy of atomization.

Answer 2

Zinc is the element which has the least energy of atomisation in d-block . It is so because in d_block zinc has 0 unpaired electron due to which it has unstable and weak metallic bonds so its energy of atomisation in d-block is least. The least energy of zinc is 126 kJ mol−1.

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