Yes it will only occur in molecure in wich it has an atom with slightly higher electronegativy and the other is the lower. And so there is a force of attraction, but no chemical bonding. Take example : water (H2O) . The hydrogen part is more positive (lower negativity) than the oxygen part (higher electronegativity) . Thus the molecule of H2O will have a force of attraction towards another H2O molecule. This also explains the adhesion chracteristic of water

Water is not a good example to use because it has hydrogen bonding between the molecules. A better example wouold be hydrogen chloride.

A dipole occurs when there is a separation of charge in an otherwise neutral molecule. As stated correctly above, any time two non-identical atoms are joined together there will be a difference in electronegativity. The more electronegative one will beome electron-rich and the one with lower electronegativity will become electron deficient.

If two polar molecules are near each other, they will have extra attacion between them becaused the dipoles attact each other. Hope this helps.