What holds solids and liquids
intermolecular forces
(Attractive forces between neighboring particles of one or more substances) pull the particles together, while kinetic energy keeps the particles at a distance and/or moving around
Phase diagram
A graphical representation of the pressure temperature relationships that apply to the equilibria between the phases of substance
Hydrogen Bond
A special type of dipole-dipole interaction that exists only in a molecules that contain a hydrogen atom bonded to a small, highly electronegative atom such as N, O or F
Ion-dipole force
Acts between an ion (either positive or negative) and a polar molecule. The degree depends on the size and charge of the ion and on the size and dipole moment of the polar molecule
Metallic solid
Are composed of metal atoms bonded together by metallic bonds
Network solid
Are covalently bonded atoms that form a continuous network
Amorphous solids
Are formed rather rapidly that its constituent particles not have time to align or organize into a more definite crystalline lattice
London Dispersion force
Are intermolecular forces of attraction that exist between all atoms and molecules. Moreover, these are the only forces acting in nonpolar molecules. They arise from the continuous movement of electrons in particles. This are attractions between an instantaneous dipole and an induced dipole
Group 8A solid
Consists of atoms of noble gases held together by London Dispersion forces
Kinetic molecular model
Explains the properties of solids and liquids in terms of intermolecular forces of attraction and the kinetic energy of yhe individual particles
Strong cohesive force
Explains why spherical water droplets form on leaves
Crystalline solids
Has a well defined crystal lattice
Ionic solid
Have ions at different points of the lattice. These ions are held together by strong coulombic forces
Lattice
Is a three dimensional system of points designating the positions of the components that make-up a crystal
Dipole-dipole force
It exist between polar molecules. Each polar molecule has unequal electron densities, resulting in a dipole-a partial positive and a partial negative
Phase boundary line
Line separating any two regions
Uniform and symmetrical
Nonpolar molecules have zero dipole moment because their electron density is ______ and ______
Phase changes
Occur with increased temperature. The particles of a solid are held close together by intermolecular forces of attraction
heat of vaporization
The amount of heat required to vaporize one mole of a substance at its boiling point. The application of hear disrupts the intermolecular forces of attraction of the liquid molecules and allows them to vaporize
Solids
The intermolecular attractive forces between their particles are stronger than those in liquids, enough to keep the solid rigid
Liquids
The particles are then free to slide over one another. This particle behavior makes liquids floe and assume the shape of their containers
Triple point
The point at which all three phase boundary lines meet
Vapor pressure
The pressure exerted by its vapor when in equilibrium with its liquid or solid
Surface Tension
The property of a liquid to resist an external force and thus assume a lesser surface area. This is attributed to the strong attractive and cohesive forces between and among the molecules, particularly at the surface of the liquid
Viscosity
The resistance of a liquid to flow. It is loosely referred to as the thickness or thinness of a liquid
Boiling point
The temperature at which its vapor pressure is equal to the external or atmospheric pressure. The boiling point of a liquid is influenced by the strength of its intermolecular force. The greater the attractive forces, the higher the energy needed to increase the kinetic energy of the molecules to break these forces
Molecular solids
has discrete covalently bonded molecules at each of its lattice points. The molecules are held together in their lattices by strong intermolecular forces, the most outstanding of which is HYDROGEN BONDING
