- Atmosphere (atm): metric unit of pressure. 1 atm= 760 mm Hg= 101.325 kPa
- Atmospheric pressure: Pressure that results for the collisions of air molecules with objects. greatest in low elevations
- Average kinetic energy: particles in a collection at any temp. have a wide range of kinetic energies. used to discuss the kinetic energy of the particles in a collection, higher temp= higher kenetic energy
- Barometers: instruments used to measure atmospheric pressure
- Boiling Point: The temperature at which the vapor pressure of the liquid is just equal to the external pressure
- Condensation: The reverse of vaporization. gas --> liquid
- Condensed states of matter: liquids and solids, have intermolecular forces (attractive forces) that occur between the particles of a solid or a liquid decrease the space between the particles, increan in pressure has little effect on the volume
- Deposition: The change of a substance from a vapor to a solid without passing through a liquid phase
- Endothermic: Heat is being added or coming in, melting
- Evaporation: liquid --> gas when it is NOT boiling, takes place more quickly at higher temps, increased kinetic energ, allows the particles to overcome intermolecular forces to escape as a gas or vapor. high energy particles leave and low energy stay behind
- Exothermic: Heat is leaving, freezing
- Freezing: Opposite of melting, liquid --> solid
- Freezing point: same as boiling point
- Gas particles: Insignifigant volume, no attractive forces, move rapidly in a constant motion, move in strait paths
- Gas Pressure: The force exerted by a gas per unit surface area of an object
- H=mc/\T: Specific Heat formula, m= mass in grams, c= specific heat in J/gC, /\T= change in temperature in C
- H=mHf: H= heat energy in joules, m= mass in grams, Hf= latent heat of fusion in J/g
- H=mHv: H= heat energy in joules, m= mass in grams, Hv= Heat of Vaporization
- Kelvin scale: no negative temerpature, kelvin temp of a substance is directly proportional to the average kinetic energy of the particles of the substance
- Kenetic Molecular Theory: The tiny particles of matter are in constant motion
- Kenetic Temperature Scale: used to reflect the relationship between the average kinetic energy, absolute zero= no molecular motion
- Kilopascals: SI unit of pressure, standard atmospheric pressure is 101.325
- Kinetic Energy: The energy an object has because of its motion
- Latent Heat fusion: amount of heat needed to melt a substance, loosens intermolecular forces, not change the temperature
- Latent Heat of Vaporization: amount of heat neded to boil a substance, used to break intermolecular forces, not change the temperature, more energy is needed to break intermolecular forces than to loosen them, need more energy to boil than to melt
- Liquids: Particles are free to flow and take the shape of their container
- Melting Point: The temperature at which vibrations of the solid molecules become strong enough to break the attractions holding them rigidly in place and allow a liquid to form
- Mm Hg or torr: The hieght of a column of mercury supported by the atmospheric pressure, standard atmospheric pressure is 760 mm Hg or 760 torr
- Normal Boiling Point: The boiling point of a sunstance at standard pressure
- Phase diagram: Gives the vonditions of temperature and pressure at whivh a substance exists as solid, liquid, & gas
- Sublimation: The change of a substance from a solid in a vapor without passing through a liquid phase
- Triple Point: Describes the only set of conditions when all the pases can exist in equilibrium
- Vacuum: The absense of any pressure due to the alck of gas particles
- Vapor Pressure: Gas molecules escape from a liquid in a sealed container, collide with the walls of the container & produce vapor pressure, gas molecules will niold up pressire and will start condensing back into a liquid, equililbrium forms same # of molecules vaporizing & conodensing so vapor pressure remains the same
- Vaporization: The conversion of a liquid to a gas or vapor
Chemistry