Question

why is electron gain enthalpy of sodium negative​

Answer 1

Answer:

if the value of ionization energy is given then its electron gain enthalpy will be a negative value of the ionization energy having the same magnitude but opposite sign. Therefore, the electron gain enthalpy of sodium cation will be negative value of the first ionization energy of the sodium atom.

Answer 2

Answer:

So, if the value of ionization energy is given then its electron gain enthalpy will be a negative value of the ionization energy having the same magnitude but opposite sign. Therefore, the electron gain enthalpy of sodium cation will be negative value of the first ionization energy of the sodium atom.

Explanation:

Because their tendency to lose electron and going to be stabilised.In this process energy liberated . But for gaining the electron we are provide some energy / heat , because we force it to gain electron whereas it's nature is to lose electron and for this the electron gain enthalpy is going to be negative.

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