Polarity Flashcards
when do polar bonds occur?
when difference in electronegativities of atoms so more electronegative atom exerts greater pulling power on shared electron pair
What is a polar bond also?
unsymmetrical
dipole
term indicates that this type of bond has two separated opposite electric charges
pure covalent
equal sharing of electrons
What does the polarity of a molecule depend on?
polar bonds it contains
way in which polar bonds are oriented (i.e. shape of molecule)
When will charges from polarity cancel out?
if bonds are of equal polarity (involve same elements) and arranged symmetrically charges oppose and cancel out
net dipole moment
if molecule contains bonds of different polarity or are asymmetrically arranged dipoles will not cancel out
permanent dipole
permanent separation of charge within bonds as result of difference in electronegativity between bonded atoms in polar molecules
dipole-dipole attraction
attraction between opposite charges on neighbouring molecules
electron domain
number of lone pairs or bond locations around a particular atom in a molecule
trend in melting/boiling points in polar compounds
higher than non-polar
dipole-diple generally stronger than london forces
solubility of polar compounds
soluble in polar solvents
van der Waals’ forces
all forces between molecules that do not involve electrostatic attractions between ions or bond formation
Where do dipole-induced dipole attractions occur?
between different molecules