Difference Between Electronegativity and Electron Affinity

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Electronegativity vs Electron Affinity

Both electronegativity and electron affinity are two different chemical properties that are associated with the elements. The primary difference between electronegativity and electron affinity lies in the fact that electronegativity is the property related to the ability of an electron to attract towards an atom. On the other hand, electron affinity is related to the release of the energy whenever an electron tends to get added to an atom. These two properties are often known to be interrelated but they are not interchangeable. Both electronegativity and electron affinity deal with the movement of the electrons. However, electronegativity is the result of the property of attraction, while electron affinity is the result of the change in energy. In this article, we will study about electronegativity vs electron affinity in detail.


Understanding the differences between electronegativity and electron affinity is important so that we do not use them interchangeably. Given below is the table that consists of the detailed differences of both the terms.


Difference Between Electronegativity and Electron Affinity

Electronegativity

Electron Affinity

Electronegativity refers to the ability of the atoms to attract the electrons from the other elements.

Electron affinity refers to the amount of energy that is liberated whenever a molecule or a neutral atom tends to acquire an electron from the other elements.

It is applied only to a single atom.

It is either applied to an atom or a molecule.

It is measured in Pauling units.

It is either measured in Kj/mol or eV.

Electronegativity is qualitative.

Electron affinity is quantitative.

It is associated with the isolated atom.

It is associated with the atom present in a molecule.

The maximum value of electronegativity is when the attracting force is high.

The maximum value of electron affinity is when the nuclear charge is more.

The most electronegative element known is Fluorine whereas, on the other hand, the least electronegative element known is Francium.

The element having the highest electron affinity is Chlorine and the element having the lowest electron affinity is Neon.

FAQ (Frequently Asked Questions)

Q1. What is the Definition of Electronegativity?

Ans: The definition of electronegativity is as follows.


Electronegativity is defined as the property possessed by an atom of an element to attract the electrons from the other elements. Electronegativity is not constant and happens because each element does not tend to attract the electrons with the same amount of force. Some elements would attract the electrons more strongly while others would not.


Hence, different elements tend to possess different electronegativities. An element which tends to possess stronger ability to attract the electrons has a higher electronegativity while the element that has a weaker ability to attract the electrons is comparatively less electronegative. Hence, the higher the electronegativity, the stronger the electron will be pulled towards the atom.

Q2. What is the Definition of Electron Affinity?

Ans: The definition of electron affinity is as explained below as follows.


Electron affinity is referred to as the change occurring in the energy of an atom. It is caused generally when there is a release of energy when an electron gets added to it. In more simple terms, electron affinity is known as the energy that is released when an atom gains an electron due to the formation of a negative ion. Electron affinity is related to the exothermic reactions and thus, whenever an electron gets added, it releases some kind of energy.

Q3. What are the Key Differences Between Electron Affinity and Electronegativity?

Ans: Given below are some of the key differences between electronegativity and electron affinity.

  1. The property due to which the electron gets attracted to the atom is known as electronegativity. On the other hand, electron affinity is related to the release of energy when an electron gets added to an atom.

  2. Electronegativity is qualitative while electron affinity is quantitative.

  3. Electronegativity is generally a unitless quantity but is defined in regards to Pauling.  Electron affinity, on the other hand, is measured in kJ/mol.

  4. When an element tends to exhibit a stronger attracting ability, the electronegativity of that element is higher. However, electron affinity is higher if the nuclear charge of the element is higher.

  5. The value of electronegativity generally lies between 0.7 to 3.98. On the other hand, electron affinity is known to be fixed since the electron releases almost a similar amount of energy when it is added to an atom.

  6. The most electronegative element known is fluorine while the element having the highest electron affinity is chlorine.