Chem Lab 18b Test 1

Vapor Pressure

pressure exerted by a vapor when it is in equilibrium with a liquid

Evaporation Rate

rate at which temperature decreases when a liquid spontaneously evaporates

(spontaneous evaporation takes heat from surroundings)

Volatile

substance that evaporates more rapidly

coordinate covalent bond

bond between a metal cation and a ligand

Coordination number

number of coordinate bonds a metal cation forms

ligand

electron pair donors that bond to a metal cation to form coordinate covalent bonds

strong electrolyte

solute present in solution almost exclusively as ions

fully dissociated in solution

solution is a good conductor of electricity

weak electrolyte

partially ionized in solution

present in solution as both ions and molecules

non-electrolyte

solute present in solution almost exclusively as molecules

solution does not conduct electric current

freezing point depression

decrease in freezing temperature is proportional to the number of moles of solute added

freezing/melting point

temperature at which the melting of a solid occurs at the same rate as the freezing of the liquid

when the rate of freezing is equal to the rate of melting (equilibrium)

supercooling

when temperature keeps declining and passes freezing point due to molecules not lining up into crystalline arrangment

colligative property

depends on ratio of solute and solvent particles (not on nature of solute)

Affects conductivity

ions per mole (more ions = more conductivity)

complete dissociation in solution

size of ions (smaller ions = move electrons with less resistance = more condutivity)

concentration (increase concentration = increase conductivity)