Question

Why ionisation is endothermic and electron gain enthalpy is exoghermic?

Answer 1

Electron Gain Enthalpy or Electron Affinity is the amount of energy released when an isolated, neutral, gaseous atom takes up an extra electron to form uninegative gaseous ions. A reaction with negative energy of reaction is termed as exothermic and those with positive energy of reaction is termed as endothermic.

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