I am so frustrated!!!!: How do you figure out the electronegativity of an element?

I know it increases form left to right and from top to bottom it decreases. But s there a formula. I mean how does Lithium=1.0 or Hydrogen equal 2.1?I am so frustrated!!!!: How do you figure out the electronegativity of an element?
Those are relative electronegativities, not absolute values.





you can calculate electronegativites from the formula:





Electronegativity = 1/2 (IE + EA)





So 0.5 multiplied by the sum of the ionization energy and electron affinity.





Both these figures can be looked up for a given atom.








Tanya:


Here is a table of Ionization Energies for atoms in the ground state.





http://en.wikipedia.org/wiki/Ionization_鈥?/a>





These energies are Kj per mole so if you want 1 atom in joules you have to multiply by 1000 and divide by Avogadro's number. This is key....





Here is link for Electron Affinities of ground state atoms:





http://en.wikipedia.org/wiki/Electron_af鈥?/a>





Again these are in KJ per mole so follow above if you want one atom..





Good Luck with Chemistry! :-)