 | Term | Definition |
| |
kinetic energy |
the energy an object has because of its motion |
| |
kinetic theory |
states that the tiny particles in all forms of matter are in constant motion |
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gas pressure |
the force exerted by a gas per unit surface area of an object |
| |
vacuum |
an empty space, with no particles and no pressure |
| |
atmospheric pressure |
results from the collisions of air molecules with objects |
| |
barometers |
devices commonly used to measure atmospheric pressure |
| |
pascal (Pa) |
SI unit of pressure |
| |
standard atmosphere (atm) |
the pressure required to support 760 mm of mercury in a mercury barometer at 25 C |
| |
vaporization |
the conversion of a liquid to a gas or vapor |
| |
evaporation |
the conversion that occurs at the surface of a liquid that is not boiling |
| |
vapor pressure |
a force due to the gas above the liquid |
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boiling point |
the temperature at which the vapor pressure of the liquid is just equal to the external pressure |
| |
normal boiling point |
boiling point of a liquid at a pressure of 101.3 kPa |
| |
phase diagram |
gives the conditions of temperature and pressure at which a substance exists as solid, liquid, and gas |
| |
triple point |
describes the only set of conditions at which all three phases can exist in equilibrium with one another |
| |
sublimation |
the change of a substance from a solid to a vapor without passing through the liquid state |
| |
surface tension |
the inward force that tends to minimize the surface area of a liquid |
| |
surfactant |
a wetting agent such as soap or detergent |
| |
aqueous solutions |
water samples containing dissolved substances |
| |
solvent |
the dissolving medium |
| |
solute |
the dissolved particles |
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solvation |
the process that occurs when a solute dissolves |
| |
electrolytes |
compounds that conduct an electric current |
| |
nonelectrolytes |
compounds that do not conduct an electric current |
| |
weak electrolyte |
only a fraction of the solute exists as un-ionized |
| |
strong electrolyte |
almost all the solute exists as separate ions |
| |
water of hydration |
water of crystallization, hydrate |
| |
effloresce |
process of losing the water of hydration |
| |
hygroscopic |
removes moisture from the air |
| |
desiccants |
hygroscopic substances are used as drying agents |
| |
deliquescent |
compounds that remove sufficient water from the air to dissolve completely and form solutions |
| |
saturated solution |
contains the maximum amount of solute for a given amount of solvent |
| |
solubility |
the amount that dissolves in a given quantity of a solvent |
| |
unsaturated |
a solution that contains less solute than a saturated solution |
| |
miscible |
two liquids that dissolve in each other |
| |
immiscible |
liquids that are insoluble in each other |
| |
Henry's law |
states that at a given temperature the solubility of a gas in a liquid is directly proportional to the pressure of the gas above the liquid |
| |
supersaturated solution |
a solution that contains more solute than it should theoretically continue to hold |
| |
concentration |
a measure of the amount of solute that is dissolved in a given quantity of solvent |
| |
dilute solution |
contains only a low concentration of solute |
| |
concentrated solution |
contains a high concentration of solute |
| |
colligative properties |
properties that only depend on the number of particles dissolved in a given mass of solvent |
| |
boiling-point elevation |
the difference in temperature between the boiling point of a solution and that of the pure solvent |
| |
freezing-point depression |
the difference in temperature between the freezing point of a solution and that of the pure solvent |
