Answer
Please see the work below.
Work Step by Step
a) Electron affinity is defined as the energy released when an electron is added to a neutral gaseous atom.
b) In a gaseous state intermolecular or inter-atomic interactions are very negligible. So the measured value of electron affinity is relatively accurate.
c) According to thermodynamic conventions energy absorbed by a system is denoted by a positive sign and energy released is denoted by a negative sign.
Ionization energy is the energy required to remove an electron from a neutral gaseous atom. The electron removal always takes place by the absorption of energy.
When an electron is added to a neutral gaseous atom, sometimes the added electron suffers repulsion, as in the case of inert gases. For inert gases, adding an electron requires energy. In such cases electron affinity is positive.
