In which of the following sets, elements are not correctly arranged with the property shown in brackets?

In which of the following sets, elements are not correctly arranged with the property shown in brackets?
  1. $\mathrm{S}\gt\mathrm{Se}\gt\mathrm{O}$ (Electron gain enthalpy)
  2. $\mathrm{F}\gt\mathrm{O}\gt\mathrm{Cl}$ (Electronegativity)
  3. $\mathrm{Na}\gt\mathrm{Li}\gt\mathrm{Al}$ (Metallic radius)
  4. $\mathrm{Na}\gt\mathrm{K}\gt\mathrm{Ba}$ (Metallic nature)

Solution

Electron gain enthalpy:- In a group there is decrease of electron gain enthalpy in general but for p-block elements only the $\mathrm{EA}_1$ of second period element is less than $\mathrm{EA}_1$ of third period element. The third period have larger size and vacant 3d orbitals, which can accommodate incoming electron easily. So order will be $\mathrm{S}\gt\mathrm{Se}\gt0$ Electronegative along a period left to right increases and in a group it is decreases. $\mathrm{F}\gt\mathrm{O}\gt\mathrm{Cl}$
Metallic radius in a periodic table from left to right it is decrease and top to bottom it is increases so, $\mathrm{Na}\gt\mathrm{Li}\gt\mathrm{Al}$
Metallic character increases down the group $\mathrm{Ba}\gt\mathrm{K}\gt\mathrm{Na}$

Asked in: AP EAMCET 2024 (22 May Shift 1)

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