Chemistry 107 Practice Exam #1 Vocabulary

Vocabulary and core concepts from the Chemistry 107 Practice Exam including gas laws, thermodynamics, and characterization of matter.

Dalton's Law of Partial Pressures

The principle expressed as $P_n = \chi_n P_{total}$, which determines the pressure of an individual gas within a mixture.

Surface Tension

The property of a liquid that allows water insects to balance on its surface without sinking.

STP (Standard Temperature and Pressure)

Conditions under which $1\,mol$ of an ideal gas occupies a volume of $22.4\,L$.

Van der Waals Equation

An equation that accounts for the finite volume of gas particles and the intermolecular attractions between them.

Effusion

The process by which gas molecules flow into a vacuum through a small hole.

Diffusion

The flow of molecules from a location of high concentration to a location of lower concentration.

Intermolecular Forces (IMF)

Forces such as dispersion and dipole-dipole forces that must be overcome during the boiling of substances like $SO_2$.

Viscosity

A term used to describe how resistant a fluid is to flowing; it typically decreases as temperature increases.

Deposition

A phase transition where a substance changes directly from a gas to a solid.

Elastic Collision

A collision between gas particles that occurs without a net loss of kinetic energy.

Vapor Pressure

A property of liquids that increases with increasing temperature and affects the determination of the boiling point.

Heat of Fusion ($\Delta H_{fus}$)

The energy required to change a substance from solid to liquid; typically the heat of vaporization ($\Delta H_{vap}$) is always greater than this value.

Phase Transition: Solid to Gas

A process achieved by either increasing the heat or reducing the pressure of a substance.