Why is the first electron affinity of oxygen positive and the second negative?
First electron affinity of oxygen is negative but second electron affinity is positive-explain. So, electron affinity of oxygen is an exothermic process and its value is negative when an extra electron is added to O- ion, that second electron experiences a force of repulsion exerted by the negative charge of the anion.
Why is the 2nd electron affinity of oxygen positive?
The second electron affinity of oxygen is positive because after adding two electrons to its neutral oxygen atom, it attains a noble gas configuration. A noble gas configuration being most stable, releases energy to decrease the total energy of the configuration.
Why is the second electron affinity ea2 of oxygen much more positive than the second electron affinity ea2 of sulfur?
Originally Answered: Why is the second electron affinity value of oxygen positive? Answer: Because you are bringing together two negative charges. There is energy released in bringing in the negative electron up to the positive nucleus.
Why is the first electron affinity negative for oxygen?
The first ionization energy, corresponding to an atom’s first electron affinity, is the energy required to remove an electron from a stable atom from its outermost shell, and is negative since the energy is released in this reaction.
Why the second affinity of oxygen is negative?
There is energy released in bringing in the negative electron up to the positive nucleus. Because the electron is negatively charged you can see that there will be repulsion between the ion and the electron making the process endothermic, hence the positive value.
Why can electron affinity be positive or negative?
Unlike ionization energies, which are always positive for a neutral atom because energy is required to remove an electron, electron affinities can be negative (energy is released when an electron is added), positive (energy must be added to the system to produce an anion), or zero (the process is energetically neutral) …
Why is ea2 always positive?
Because the electron is negatively charged you can see that there will be repulsion between the ion and the electron making the process endothermic, hence the positive value. The reason why it can happen is that this is just one energy change in a whole series which may occur during a reaction.
Why is 2nd electron affinity endothermic?
2nd Electron Affinity is always endothermic since an additional electron is added to a negative ion. Energy is absorbed to overcome inter-electronic repulsion between two negatively charged species.
What is 2nd electron affinity?
The second electron affinity is the energy required to add an electron to each ion in 1 mole of gaseous 1- ions to produce 1 mole of gaseous 2- ions. This is more easily seen in symbol terms. X−(g)+e−→X−2(g) It is the energy needed to carry out this change per mole of X−.
Why is the second electron affinity for elements positive while the first one is negative?
Why is second electron affinity endothermic?
Why is the electron affinity negative?
Electron affinities are negative numbers because energy is released. The elements of the halogen group (Group 17) gain electrons most readily, as can be seen from their large negative electron affinities. This means that more energy is released in the formation of a halide ion than for the anions of any other elements.