Chapter 12: Liquids, Solids and Intermolecular Forces Flashcards
List the physical property differences between solids, liquids and gases for shape, volume, density and compressibility.
Gases have variable shape and volume. Small density, lots of compressibility, motion and space. liquids have variable shape and constant volume. Has a density that is less than solids and small compressibility. has some motion and are close together. Solids have constant shape and volume; they have large density and no compressibility. Less motion than a liquid and are close together
Explain how these physical property differences are related to the motion and spacing of atoms, ions, or molecules.
In solids, atoms have very little motion. In liquids have some motion and gases have lots of motion
Define attractive force
forces between particles that draw them together
Describe how the differences in attractive forces between the physical states of matter
account for the differences in their physical properties.
There is strong IMF in solids. Weak IMF in liquids. No IMF in gases
Changing the amount of kinetic energy (heat) present changes the physical state of a
substance.
The changes in physical state, called phase changes, are represented in a heating/cooling curve which are also called a phase change graph.
Define melting point.
when a solid changes to a liquid because heat is added
define freezing point
when a liquid changes to a solid because heat is taken away
Define vaporization
when a liquid changes to a gas because heat is added
Define condensation
when a gas changes to a liquid because heat is taken away
define sublimination
when a solid changes to a gas because heat is added
Explain how a London dispersion force (an instantaneous dipole which induces a dipole force) leads to intermolecular attraction in a liquid
When electrons are on one side of the atom, the electrons of another atom is attracted to the exposed nucleus.
Explain the circumstances required for the formation of a special type of intermolecular dipole-dipole force (intermolecular attraction) called hydrogen bonding.
Happens when a molecule that consists of a hydrogen bonded to either F, N, O is bonded with another molecule that contains F, N, O
On a drawing of the structural formula of several molecules, indicate the hydrogen bonding attraction, if any, between the molecules.
Hydrogen bonding showed with dotted lines or dashed lines
Given a structural formula, identify the major type of intermolecular attraction between identical molecules
Dipole-Dipole attraction attracts polar molecules together. London Dispersion attracts non-polar molecules together. Hydrogen bonding bonds molecules that have hydrogen and F, O, N with another molecule that has F, O, N
Describe surface tension (a liquid property)
the amount of force required to expand surface of a liquid. A fluid surface has the tendency to occupy little surface.
