How do you calculate electronegativity of an element?
The trend and difference in electronegativity determines that. (How much the element wants an electron).
The higher the attraction for an electron, the higher the electronegativity.
Electronegativity increases as you move left to right, and down to up on the periodic table (fluorine is the most electronegative element on the periodic table).
If the difference in electronegativity is:
# <0.5 ->#it's a non-polar bond (electrons equally shared)
#0.5 - 1.7 ->#it's a polar covalent bond (2 nonmetals, electrons unequally shared)
#> 1.7 ->#it's ionic (metal and nonmental)
I hope this helps