The molar enthalpy change accompanying the removal of an electron from a gas phase atom or ion in its ground state is called?

The molar enthalpy change accompanying the removal of an electron from a gas phase atom or ion in its ground state is called Ionization Enthalpy. Ionization Enthalpy refers to the amount of energy required to remove one electron from an atom or ion in its ground state to form a positively charged ion. In other words, it is the energy required to "ionize" an atom or ion. For example, to remove an electron from a neutral hydrogen atom to form a positive hydrogen ion (H+) requires a certain amount of energy. This energy is called the ionization enthalpy of hydrogen. Similarly, the ionization enthalpy can be defined for any other atom or ion.