Question

ELECTRON GAIN ENTHALPY OF SECOND AND FIFTEENTH GROUP ELEMENTS ARE LESS POSITIVE.WHY?

Answer 1

Answer:

Electron gain enthalpy of an element is the energy released when a neutral isolated gaseous atom accepts an extra electron to form the gaseous negative Ion i.e. anion. We can denote it by Δ egH. Greater the amount of energy released in the above process, higher is the electron gain enthalpy of the element.

The electron gain enthalpy of an element is a measure of the firmness or strength with which an extra electron is bound to it. It is measured in electron volts per atom or kJ per mole. It can be an endothermic or exothermic reaction when you add an electron to the atom.