Chapter 7, Problem 23PS

Interpretation Introduction

Interpretation:

The given elements have to be arranged in increasing order of size.

Concept Introduction:

Atomic radius: The concept explain chemical element is a measured of the size of its atoms, in other words to measure the distance from the center of the nucleus to the boundary of the surrounding cloud of number of electrons.

Increase and decrease electronegativity: The less vacancy electrons an atoms has the least it will gain of electrons. Moreover the electron affinity decrease down the groups and from right to left across the periods on the periodic table, the reason is electrons are placed in a higher energy level far from the nucleus thus a decrease from its pull.

Electron attachment enthalpy: ${\Delta }_{EA}H$ is defined as the enthalpy change occurring when a gaseous atom adds an electron forming a gaseous anion.

  $\text{A(g)}\text{+}{\text{e}}^{\text{-}}\to {\text{A}}^{\text{-}}\text{(g)}\text{----}\text{Electron}\text{attachment}\text{enthalpy}{\text{=Δ}}_{\text{EA}}\text{H}$