genchem2

• Kinetic Molecular Model is used to explain the properties of liquids and solid molecules, as well as the forces of attraction that account for such properties.
• The kinetic energy of a particle is the energy needed for the particles to keep moving, which is dependent upon temperature.
• Temperature and kinetic energy is directly proportional. ● If the temperature goes up, the kinetic energy also goes up.
• Particles of solids are tightly packed, vibrating about a fixed position.
• Solids have a definite shape and definite volume.
• CRYSTALLINE SOLIDS - molecules are arranged in a geometric pattern
• AMORPHOUS SOLIDS - molecules do not have a set pattern of arrangement
• According to the kinetic theory, the motion of solid particles can be described as lower kinetic energy, less motion, more packed particles, and higher intermolecular forces
• Intermolecular forces between particles are therefore much more effective in solids.
• These hold particles of a solid in relatively fixed positions, with only vibrational movement.
• Solids are more ordered than liquids and gases.
• According to the kinetic theory, motion of liquid particles can be described as a form of matter that has a definite volume and takes the shape of its container.
• Particles in a liquid are in constant motion however, the particles in a liquid are closer together than the particles in a gas are therefore, the attractive forces between particles in a liquid are more effective than those between particles in a gas.
• Particles of liquids are tightly packed, but are far enough apart to slide over one another.
• The liquids have an indefinite shape and a definite volume.
• This attraction is caused by intermolecular forces.
• According to the kinetic molecular theory of liquids, the particles are not bound together in fixed positions.
• Particles of gases are very far apart and move freely
• Gases have an indefinite shape and an indefinite volume.
• A plasma is an ionized gas.
• A plasma is a very good conductor of electricity and is affected by magnetic fields
• Plasma, like gases have an indefinite shape and an indefinite volume.
• Matter is made up of particles that are constantly moving
• All particles have energy, but the energy varies depending on the temperature the sample of matter is in. This in turn determines whether the substance exists in the solid, liquid, or gaseous state.
• Molecules in the solid phase have the least amount of energy, while gas particles have the greatest amount of energy.
• The temperature of a substance is a measure of the average kinetic energy of the particles
• A change in phase may occur when the energy of the particles is changed.
• There are attractive forces between atoms/molecules, and these become stronger as the particles move closer together. These attractive forces are called intermolecular forces
• Phase change is a change from one state of matter to another.
• Phase changes are physical changes because they do not affect the chemical make up of a substance.
• During a phase change heat energy is either absorbed or released
• EXOTHERMIC - Heat is released as molecules slow down and move closer together.
• ENDOTHERMIC - Heat energy is absorbed as molecules speed up and expand.
• A phase diagram illustrates the changes in the phase of a matter under varying temperature and pressure conditions.
• INTRAMOLECULAR FORCE - forces within a molecule
• INTERMOLECULAR FORCE - Forces between different molecules (atoms or ions)
• NONPOLAR MOLECULES - Occurs when the electrons are evenly distributed.
• NONPOLAR MOLECULES - When atoms have the same or similar electronegativity.
• POLAR MOLECULE - Occurs when two atoms do not share electrons equally in a covalent bond.
• POLAR MOLECULE - Happens when there is a difference between the electronegativity values of each atom.