Ch 13 - Properties of Mixtures

Question 1

like dissolves like

Answer 1

substances with similar IMF dissolve in each other

Question 2

ΔHsoln

Answer 2

energy related to making a solution
ΔHsoln = ΔHsolute + ΔHsolvent + ΔHmix
ΔHsoln = ΔHlatt + ΔHhydr

Question 3

ΔHsolute

Answer 3

energy to seperate solute particles
endothermic

Question 4

ΔHsolvent

Answer 4

energy to seperate solvent particles
endothermic

Question 5

ΔHmix

Answer 5

solute and solvent mix
exothermic (forming new IMF)

Question 6

ΔHlatt

Answer 6

breaking attractive forces
endothermic

Question 7

ΔHhydr

Answer 7

ΔHsolvation with the solvent is water
exothermic (forming new ion-dipole IMF)
increases with charge and decreases with size

Question 8

ΔHsolvation

Answer 8

ΔHsolvent + ΔHmix
surrounding something with solvent particles

Question 9

entropy (S)

Answer 9

ways to distribute a system’s energy
solution only forms if ΔSsoln > ΔHsoln

Question 10

entropy of states of matter

Answer 10

Sgas > Ssolid

Question 11

entropy of solution vs solute and solvent

Answer 11

Ssolution > Ssolute and Ssolvent

Question 12

systems favor

Answer 12

lower enthalpy (H) and higher entropy (S)

Question 13

saturated solution

Answer 13

at equilibrium, max amound of dissolved solute is present in the presence of undissolved solute
more solute would not dissolve

Question 14

unsaturated solution

Answer 14

lower than equilibrium concentration of dissolved solute
more solute would dissolve

Question 15

supersaturated solution

Answer 15

more than equilibrium concentration
will readily recrystallize

Question 16

effect of temperature on solubility of solids

Answer 16

increasing temperature, increasing solubility

Question 17

effect of temperature on solubility of gases

Answer 17

increase temperature, decrease solubility

Question 18

effect of pressure on solubility of gases

Answer 18

increasing pressure, increasing solubility

Question 19

henry’s law

Answer 19

Sgas = kH * Pgas

Question 20

molarity (M)

Answer 20

mols solute/L solution

Question 21

molality (m)

Answer 21

mols solute/kg solvent

Question 22

mass %

Answer 22

mass solute/(mass solute + mass solvent)

Question 23

ppm

Answer 23

parts per million
mg/L

Question 24

ppb

Answer 24

parts per billion
µg/L

Question 25

electrolyte

Answer 25

conducts electric current
dissociates/ionizes
acids, bases, soluble ionic compounds

Question 26

nonelectrolyte

Answer 26

does not dissociate or conduct electric current

Question 27

raoult’s law (VP lowering)

Answer 27

VP of pure solvent ° > VP of solvent in solution
Psolvent = Xsolvent * P°solvent
fewer solvent particles on the surface, so fewer need to vaporize to maintain equilibrium

Question 28

boiling point elevation

Answer 28

fewer particles on the surface available to vaporize, need to increase temperature to increase vaporization to balance condensation
Tbsoln - Tbsolvent = iKbmolality

Question 29

freezing point depression

Answer 29

fewer solvent particles on the surface available to freeze, need to lower temperature to increase freezing to balance melting
Tfsolvent - Tfsoln = iKfmolality

Question 30

i

Answer 30

ions per formula unit

Question 31

osmotic pressure

Answer 31

solutions of higher and lower concentration will experience flow of solvent into more concentration solution
pi = M * R * T