Unit 4: IMFs & Thermodynamics Flashcards
forces between particles (atoms, molecules, or ions) of a substance are called ________________
intermolecular forces
bonds within molecules or formula units are called __________________
intramolecular forces
the dominant forces between molecules are _____________
electrostatic
dispersion forces are __________ and _____________ attractive forces between _____________ dipoles
very weak, very short range, temporary (induced)
dispersion forces are the only forces between ___________ molecules
nonpolar
dispersion forces are also called
London forces, van der Waals, or induced dipoles
dispersion forces are __________ rather than ______________ dipole-dipole interactions
temporary; permanent
polarizability ___________ with increasing numbers of electrons and, therefore, with increasing sizes of molecules
increases
London forces are generally ____________ for molecules that are larger or have more electrons
stronger
IMF result from attractive forces between regions of ____________ and ____________ charge density in neighboring molecules
positive, negative
_________ interactions are so strong, they can even be considered intermolecular forces as well as intramolecular forces
ionic
surface tension describes the inward forces that must be overcome in order to ________ the surface area of a liquid
expand
viscosity increases as IMFs __________ in strength and as the temperature __________
increase; decreases
the vapor pressure of all liquids ___________ with temperature
increases
at room temperature, a liquid with ______ vapor pressure is called volatile
high
diamond is a __________ crystal of carbon
covalent
diamond and graphite are two _____________ forms of carbon
crystalline
graphite forms __________ while diamond is ______________
flat sheets; tetrahedral
the electrons in metallic solids are _____________
delocalized to form a “sea of electrons” that allow electricity (the movement of electrons) to flow freely
First Law of Thermodynamics: During any physical or chemical change, the total amount of energy in the universe is __________
conserved (Law of Conservation of Energy)
Total energy = __________ + ____________
kinetic energy, potential energy
Total energy = __________ = ___________ + ___________
internal energy, heat energy, work energy
State functions are a property of the system whose value depends ONLY on the __________ and ___________ states of system
initial, current
(symbols are capital letters)
usually the reaction: the reactants and products
system
the rest: the beaker, the air in the room, etc
surroundings
system + surroundings
universe
open system
exchange energy & matter
closed system
exchange energy only
isolated system
no exchange of energy or matter
isothermal
constant temperature
adiabatic
constant heat
isobaric
constant pressure