GENERAL CHEMISTRY TWO

GENERAL CHEMISTRY TWO

LESSON ONE: INTERMOLECULAR FORCES OF LIQUIDS AND SOLIDS

KINETIC MOLECULAR THEORY

One. All particles are composed of very small particles called atoms or molecules.

Two. The distances between gas particles are so great that the volume of the gas is mostly empty space.

Three. There are no repulsive or attractive forces between gas particles.

Four. These particles are in constant random motion.

Five. The kinetic energy of the particles depends on the temperature of the gas.

A Molecule will be Nonpolar if:

. All of the terminal atoms (or groups) are the same.

. All of the terminal atoms (or groups) are symmetrically arranged around the central atom.

. The terminal atoms (or groups) have the same charges.

A Molecule will be Polar if:

. One or more terminal atoms differ from each other

. At least one polar bond is present

. The terminal atoms are not symmetrically arranged

. The molecule has one slightly positive end one slightly negative end

+

. An increase in temperature results in increased kinetic energies of gases dissolving in liquid.

. This increased motion enables the dissolved gas to break intermolecular forces with the solvent, and escape the solution.

Example:

A warm bottle of carbonated drink does not taste as good as a cold one, because there is less carbon dioxide dissolved in the warm bottle.