57 terms

States of Matter

Spontaneous mixing of the particles of two substances caused by their random motion
Process by which gas particles under pressure pass through a tiny opening
elastic collision
Collision between gas particles and between particles and container walls. These collisions have no net loss of kinetic energy
Gas particles glide easily past one another. Both liquids and gases flow so they are both considered this. These take the shape of their container.
ideal gas
An imaginary gas that perfectly fits all the assumptions of the kinetic-molecular theory.
kinetic-molecular theory
Particles of matter are always in motion.
real gas
A gas that does not behave completely according to the assumptions of the kinetic-molecular theory
atmosphere of pressure
Exactly 760 mm Hg.
Device used to measure atmospheric pressure.
millimeter of mercury
A common unit of pressure, symbolized by mm Hg.
It is the force that will increase the speed of one kilogram mass by one meter per second each second it is applied. It is the SI unit of force.
The pressure exerted by a force of one newton (1N) acting on an area of one square meter.
standard temperature and pressure
For purposes of comparison, scientists have agreed on standard conditions of exactly 1 atm pressure and 0°C. These conditions are commonly abbreviated STP.
absolute zero
-273.15°C or 0 K. The theoretical lowest temperature possible to achieve.
Boyle's law
The volume of a fixed mass of gas varies inversely with the pressure at constant temperature. (simply - when volume goes up the pressure goes down, and when volume goes down the pressure goes up when temperature is kept constant)
Charles's Law
The volume of a fixed mass at constant pressure varies directly with the Kelvin temperature (simply - when the temperature goes up the volume goes up, when the temperature goes down, the volume goes down if pressure is constant)
combined gas law
Expresses the relationship between pressure, volume, and temperature of a fixed amount of gas.
Dalton's Law of partial pressures
The total pressure of a mixture of gasses is equal to the sum of the partial pressures.
gas laws
Simple mathematical relationships between the volume, temperature, pressure, and quantity of a gas.
Gay-Lussac's Law
The pressure of a fixed mass of gas at constant volume varies directly with the Kelvin Temperature. (simply - pressure goes up with the temperature, and down with temperature if volume is kept constant)
partial pressure
The pressure of each gas in a mixture.
Avogadro's law
Equal volumes of gases at the same temperature and pressure contain equal numbers of molecules.
Gay-Lussac's law of combining volumes of gases
At constant temperature and pressure, the volumes of gaseous reactants and products can be expressed as ratios of small whole numbers
standard molar volume of a gas
The volume occupied by one mole of a gas at STP. This has been found to be 22.41410 L.
ideal gas constant
The constant R.
ideal gas law
The mathematical relationship of pressure, volume, temperature, and the number of moles of a gas.
capillary action
The attraction of the surface of a liquid to the surface of a solid.
The process by which particles escape from the surface of a nonboiling liquid and enter the gas state.
surface tension
A force that tends to pull adjacent parts of a liquid's surface together, thereby decreasing surface area to the smallest possible size.
amorphous solid
The particles are arranged randomly.
crystal structure
The total three-dimensional arrangement of particles of a crystal.
The physical change of a solid to a liquid by the addition of heat.
supercooled liquid
Substances that retain certain liquid properties even at temperatures at which they appear to be solid.
The physical change of a liquid to a solid by removal of heat.
The process by which a liquid or solid changes to a gas.
A substance in which the particles are arranged in an orderly, geometric, repeating pattern.
crystalline solid
Most solids are this. They consist of crystals.
melting point
The temperature at which a solid becomes a liquid.
unit cell
The smallest portion of a crystal lattice that shows the three-dimensional pattern of the entire lattice.
The conversion of a liquid to a vapor within the liquid as well as at its surface. It occurs when the equilibrium vapor pressure of the liquid equals the atmospheric pressure.
boiling point
The temperature at which the equilibrium vapor pressure of the liquid equals the atmospheric pressure.
The process by which a gas changes to a liquid.
critical point
Indicates the critical temperature and critical pressure.
critical pressure
The lowest pressure at which the substance can exist as a liquid at the critical temperature.
critical temperature
The temperature above which the substance cannot exist in the liquid state.
The change of state from a gas directly to a solid.
A dynamic condition in which two opposing changes occur at equal rates in a closed system.
equilibrium vapor pressure
The pressure exerted by a vapor in equilibrium with its corresponding liquid at a given temperature.
freezing point
The temperature at which the solid and liquid are in equilibrium at 1 atm pressure.
Le Chatelier's principle
When a system at equilibrium is disturbed by application of a stress, it attains a new equilibrium position that minimizes the stress.
Molar heat of fusion
The amount of heat energy required to melt one mole of solid at its melting point.
molar heat of vaporization
The amount of heat energy needed to vaporize one mole of liquid at its boiling point.
Any part of a system that has uniform composition and properties.
phase diagram
A graph of pressure versus temperature that shows the conditions under which the phases of as substance exist.
The change of state from a solid directly to a gas.
triple point
Indicates the temperature and pressure conditions at which the solid, liquid, and vapor of the substance can coexist at equilibrium.
volatile liquid
Liquids that evaporate readily.