Electronegativity Flashcards
Define the term electronegativity
The ability of an atom to attract the bonding electrons in a covalent bond
Trends?
Increases across period
Decreases down group (except noble gases)
Diatomic gases are…
Non-polar :
atoms have equal electronegativities so are equally attracted to both nuclei
Define term dipole?
A difference in charge between the 2 atoms caused by a shift in electron density in the bond
The greater the difference in electronegativity…
the greater the shift in electron density + the more polar the bond
If the polar bonds are arranged so they point in opposite directions…
(e.g. CO2)
they’ll cancel out : non-polar
If polar bonds point roughly in SAME direction…
e.g. CHCl3
molecule will be POLAR
because polar bonds are not orientated so they are pointing in opposite directions so they don’t cancel each other out
Electronegativity measured using…
Pauling scale
