Bonding and Structure

Question 1

Polar molecule

Answer 1

A molecule with an overall dipole, taking into account any dipoles across bonds.

Question 2

Permanent Dipole

Answer 2

A small charge difference across a bond resulting from a difference in electronegativities of the bonded atoms.

Question 3

Permanent Dipole-Dipole Force

Answer 3

An attractive force between permanent dipoles in neighbouring polar molecules.

Question 4

Polar Covalent Bond

Answer 4

A bond with a permanent dipole.

Question 5

Intermolecular Force

Answer 5

An attractive force between neighbouring molecules. Intermolecular forces can be Van Der Waals’ forces (induced dipole-dipole forces), permanent dipole-dipole forces or hydrogen bonds.

Question 6

Hydrogen Bond

Answer 6

A strong dipole-dipole attraction between an electron-deficient hydrogen atom (O-H&+ or N-H&+) on one molecule and a lone pair of electrons on a highly electronegative atom (H-O:&- or H-N:&-) on a different molecule.

Question 7

Electronegativity

Answer 7

A measure of the attraction of a bonded atom for the pair of electrons in a covalent bond.

Question 8

Covalent Bond

Answer 8

A bond formed by a shared pair of electrons.

Question 9

Van Der Waals’ Forces

Answer 9

Very weak attractive forces between induced dipoles in neighbouring molecules.

Question 10

Dative Covalent Bond

Answer 10

A shared pair of electrons which has been provided by one of the bonding atoms only; also called a coordinate bond.

Question 11

Delocalised Electrons

Answer 11

Electrons that are shared between more than two atoms.