Ch 9: Solutions

Question 1

solutions

Answer 1

homogeneous mixtures composed of two or more substances

combine to form a single phase, generally liquid

Question 2

____ particles surround ____ particles via electrostatic interactions in a process called solvation or dissolution

Answer 2

solvent

solute

Question 3

aqueous solutions are more important for the MCAT, solvation in water is called

Answer 3

hydration

Question 4

most dissolutions are _____ but gas is _____

Answer 4

endothermic

exothermic

Question 5

solubility

Answer 5

maximum amount of a solute that can be dissolved in a given solvent at a given temperature; often expressed as molar solubility which is the molarity of the solute at saturation

Question 6

complex ions or coordination compounds are

Answer 6

composed of metallic ions bound to various neutral compounds and anions, referred to as ligands

Question 7

formation of complex ions increases the _____ of otherwise insoluble ions (opposite of the ____ )

Answer 7

solubility

common ion effect

Question 8

process of forming a complex ion involves e- pair donors and e- pair acceptors such as those seen in

Answer 8

coordinate covalent bonding

Question 9

percent concentration by mass

Answer 9

mass solute / mass solution x 100

used for aq solutions and solid-in-solid solutions

Question 10

mole fraction

Answer 10

moles solute/ total moles

used for vapor pressure depression and partial pressure of gases in a system

Question 11

molarity

Answer 11

moles solute / liters of soln

used for rate laws, law of mass action, osmotic pressure, , pH and pOH, Nernst equation

Question 12

molality

Answer 12

moles solute / kg of solvent

used for boiling point elevation and freezing point depression

Question 13

normality

Answer 13

number of equivalents / liters of solution

molarity of the species of interest and is used for acid-base and oxidation-reduction reactions

Question 14

solubility product constant Ksp

Answer 14

equilibrium constant for a dissolution reaction

Question 15

comparison of the ion product (IP) to Ksp determines

Answer 15

the level of saturation and behavior of the solution

Question 16

IP

Answer 16

solution is unsaturated, if more solute were added it will dissolve

Question 17

IP = Ksp

Answer 17

solution is saturated (at equilibrium) and there will be no change in the concentrations

Question 18

IP > Ksp

Answer 18

solution is supersaturated, and a precipitate will form

Question 19

formation of a complex ion in solution greatly increases

Answer 19

solubility

Question 20

formation or stability constant (Kf)

Answer 20

equilibrium constant for complex formation. its value is much greater than Ksp usually

Question 21

formation of complex ions inc solubility of other salts containing same ions bc it uses products of those dissolution reactions, shifting equilib to the

Answer 21

right, opposite of the common ion effect

Question 22

common ion effect

Answer 22

dec solubility of a compound in a solution that already contains one of the ions in the compound; presence of that ion in soln shifts the dissolution reaction to the left, decreasing its dissociation

Question 23

colligative properties

Answer 23

physical properties of solutions that depend on the conc of dissolved particles but not on their chemical identity

Question 24

vapor pressure depression follows

Answer 24

Raoult’s Law

Question 25

Raoult’s Law

Answer 25

presence of other solutes dec the evaporation rate of a solvent without affecting its condensation rate, thus decreasing its vapor pressure

vapor pressure depression also explains boiling point elevation- as the vapor pressure decreases the temperature (energy) required to boil the liquid must be raised

Question 26

osmotic pressure

Answer 26

primarily dependent on the molarity of a solution

Question 27

freezing point depression and boiling point elevation

Answer 27

shifts in the phase equilibria dependent on the molality of the solution

Question 28

for solutes that dissociate, the van’t Hoff factor (i) is

Answer 28

used in freezing point depression, boiling point elevation, and osmotic pressure calculations