Question

What is the basic difference between the term electron gain enthalpy and electronegativity?

Among the elements of the second period Li to Ne pick out the element: (i) with the highest first ionisation energy (ii) with the highest electronegativity (iii) with the largest atomic radius Give the reason for your choice.

Electronegativity, described by Linus Pauling described as 'The power of an atom in a molecule to attract electrons to itself' (Pauling in The nature of the chemical, is used to predict bond polarity. There are dozens of methods for empirically quantifying electronegativity including: the original thermochemical technique, numerical averaging of the ionisation potential and electron affinity, effective nuclear charge and covalent radius analysis and the averaged successive ionization energies of an element's valence electron etc. Indeed, there are such strong correlations between numerous atomic parameters—physical and chemical—that the term 'electronegativity' integrates them into a single dimensionless number between 0.78 and 4.00 that can be used to predict/describe/model much of an element's physical character and chemical behaviour.

PASSAGE II Read the passage given below and answer the following questions: In the periodic table electronegativity increases from left to right in a period and decreases from top to bottom in a group. The non-metallic character of an element is directly related to the electronegativity while the metallic character is inversely related to it.