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Front 1

Polar Molecule

Back 1

molecules with an overall dipole when you take into account any dipoles across the bond.

Front 2

Dipole

Back 2

a small charge difference across a bond resulting from a difference in electronegativities between the bonded molecules. E.g HCl

Front 3

Instantaneous Dipole

Back 3

Electrons are constantly in motion so at any particular time they may not be evenly distributed so one end is slightly negative and a dipole arises e.g Cl2

Front 4

Nucleophile

Back 4

A molecule or negatively charged ion with a lone pair of electrons that can be donated to a positively charged atom to form a covalent bond.

Front 5

Substitution reaction

Back 5

A reaction in which one atom or group in a molecule is replaced by another atom or group

Front 6

Non Polar Bonds

Back 6

In a covalent bond where the two bonding atoms are the same, the electrons are shared equally so the bond is non polar.

Eg. H-:-H

Front 7

Polar Bonds

Back 7

In a covalent bond where the bonding atoms do not share the electrons equally due to differences in electronegativity, atom size or nuclear charge. More electronegative atoms attract the shared electrons more becoming slightly negatively charged and the other slightly positive.

Front 8

Polar molecules

Back 8

A molecule with an overall dipole when you take into account any dipoles across the bond.

Front 9

Factors for a polar molecule

Back 9

1) Big difference in electronegativities

2) Non symmetrical shape

Front 10

Electronegativity

Back 10

A measure of how strongly a covalently bonded atom attracts the shared pair of electrons to itself.

Front 11

Dipole

Back 11

A molecule with a positive end and a negative end because of its polar bonds.

Front 12

Dipole-Dipole Force

Back 12

An attractive force between dipoles in neighbouring molecules.

Front 13

Permanent Dipole

Back 13

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

Front 14

Intermolecular Force

Back 14

Eg. VDWF/ Permanent dipole-dipole force

An attractive force between neighbouring molecules.

Front 15

Permanent Dipole - Permanent Dipole Force

Back 15

An attractive force between permanent dipoles in neighbouring molecules.

Front 16

Instantaneous Dipole - Induced Dipole Force

Back 16

-Weakest Type of intermol. Bond

-The more electrons the atom has the greater the dipole effect

-Same in larger atoms as they have more electrons

Front 17

Types Of Dipole: Instantaneous Dipole

Back 17

Oscillations of electrons within the shell mean that at any moment the distribution of charge may be uneven. One part of the molecule will be slightly negative and the other slightly positive

Front 18

Types Of Dipole: Induced Dipole

Back 18

Occurs if an unpolarised molecule is near a dipole. The dipole attracts or repels electrons in the unpolarised molecule, inducing a dipole.

Front 19

MP & BP of Halogens

Back 19

The melting and boiling points of halogens increases down the group because at the top there are fewer electrons and the atoms is much smaller so there are weak VDWF which are easy to overcome.

Front 20

Mp & Bp of Alkanes

Back 20

In Alkanes the longer the chain, the stronger the intermol. forces and the higher the boiling point.

In straight chain Alkanes there are more contacts between molecules and so more chances to form intermol. bonds. Thus straight chain Alkanes have higher boiling points.

Front 21

Ammonia as a nucleophile

Back 21

The haloalkane is heated in a sealed tube with concentrated ammonia solution.

The product is an amine with an NH2 group.

Front 22

Factors affecting the rate of hydrolysis

Back 22

Polarity of the C-Halogen bond

Bond enthalpy of the C-Halogen bond (bond enthalpy is more important)

Hint 22

2

Front 23

Common nucleophiles

Back 23