Question

How to find the electronegativity of a particular element ? Suppose how to find the electronegativity of chlorine and nitrogen?? Please explain.

Answer 1

There are different methods to find electronegativity of an element.
First of all electronegativity is a reative value which change its value for the same element when calculated using different method.One method is given below, Finding electronegativity using Mulliken Electronegativity 1.)Find the first ionization energy of your atom.
To find Mulliken electronegativity for a certain atom, find that atom's first ionization energy. This is the energy required to make the atom discharge a single electron.
This is something you'll probably have to look up in chemistry reference materials.
As an example, let's say that we're trying to find the electronegativity of lithium (Li). In the table on the site above, we can see that its first ionization energy is 520 kJ/mol.

2.)Find the electron affinity of the atom.
This is a measure of the energy gained when an electron is added to an atom to form a negative ion. Again, this is something you'll need to look up in reference material.
The electron affinity of lithium is 60 kJ mol^-1.

3.)Solve the Mulliken electronegativity equation.
When you're using kJ/mol as units for your energies, the equation for Mulliken electronegativity is EN_Mulliken = (1.97×10⁻³)(E_i+E_ea) + 0.19. Plug your values into the equation and solve for EN_Mulliken.
In our example, we would solve like this: EN_Mulliken = (1.97×10⁻³)(E_i+E_ea) + 0.19 EN_Mulliken = (1.97×10⁻³)(520 + 60) + 0.19 EN_Mulliken = 1.143 + 0.19 = 1.333


For finding electronegativity of Cl or N plug in their first ionization energy,electron affinity in the above equation,which gives you the relative value.