Ca(NO3)2

YESAll nitrates are soluble!

Zn(OH)2

NOHydroxides are insoluble except for sodium and potassium ions!

K3PO4

YES Phosphates are insoluble except for sodium, potassium, and ammonium ions!

Ene

rgy

to b

oil (

kJ/m

ol)

1100

Ion-ion

700

500

Covalent bonds

100

60

Intermolecular forces

0.1

H-bonds

Polar bonds

Non-polar bonds

(intramolecular forces)

Why so strong?

-Small size of hydrogen

-High electronegativity of O, N, and F

What are they?

-A network between H and either N, O, or F molecules

NameName Simple CubicSimple Cubic Body-Body-Centered Centered CubicCubic

Face-Face-Centered Centered CubicCubic

# atoms/unit # atoms/unit cellcell

11 22 44

VolumeVolume

e = edge e = edge lengthlength

r = cell r = cell

radiusradius

ee33 = (2r) = (2r)33 = 8r = 8r3 3 ee33 = =

(4r/√3)(4r/√3)3 3

ee33 = =

(4r/√2)(4r/√2)33

For:

3A(aq) + B(s) ↔ 2C(g) + D(l) + E(aq)

** Only gaseous and dissolved particles are expressed in the equilibrium expression because their concentrations can vary (whereas solids and liquids cannot)

2

3

[ ] [ ]

[ ]c

C EK

A

If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change.

3A(aq) + B(s) ↔ 2C(g) + D(l) + E(aq)

If the concentration of A is raised, as the mixture returns to equilibrium a portion of all of the reactants are consumed, and as a result, the concentrations of C, D, and E will increase

N2 + O2 ↔ 2NOI

C

E

0.25 0.25 0.0042

-x -x +2x

0.25 0.25 0.0042 + 2x

Kc = 1.7 x 10-3 = (0.0042 + 2x)2 / (0.25)(0.25)

Eventually… x = 0.0030 M change

Would a precipitate form?

AgCl(s) ↔ Ag+(aq)+ Cl-(aq)

Ksp = 1.8 x 10-10

Q = [Ag+][Cl-]

25 mL of 0.1M AgNO3 solution is added to 100 mL of 0.0050M NaCl solution

If Q<Ksp, no precipitation

If Q>Ksp, precipiation

[Ag+] = 0.10M(25mL/125mL)

[Cl-] = 0.005M(100mL/125mL)

Therefore Q>Ksp, and this is expected to precipitate

Q = (0.100)(0.005) = (5.0 x 10-4)

Molar Concentration “molarity”

M = # moles/vol. of solution

Molal Concentration “molality”

m = # moles solute / mass of solvent (in kg)

Mass Fraction

= mass solute / mass total

Ppm (parts per million)

= mass solute (in mg) / mass total (in kg)

Mole Fractions

XA = molesA/molesA + molesB +…

Cd(OH)2 Ksp = 1.2 x 10-14

Ca(OH)2 Ksp = 7.9 x 10-6

Ca2+

Cd2+

0.10 M Cd2+

0.10 M Ca2+

At what concentration of OH- will one of the ions precipitate?

(OH-) is more attracted to Cd2+, because, as the equations are similar in structure (1 cation, 2 anions) they are comparable and Cd(OH)2 would precipitate first

Cd(OH)2 Cd2+(aq) + 2OH-

(aq)

0.10 ~0

+x +x

Ksp = 1.2*10-14 = (0.10)(x)2

X2 = 12*10-12

x = 3.5*10-6

Freezing Point Depression

ΔTf = iKfm

Boiling Point Elevation

ΔTb = iKbmi = # dissociated particles in empirical formula (Van’t Hoff factor)

Kf or Kb = boiling point elevation / freezing point depression constant

m = (n mol solute / mass solvent (kg))

Volatile SolutionPvaptotal = XAPvapA + XBPvapB +…

Non-volatile Solution

PvapA = XAPvapA + 0

volatile= changes to gas

“the solubility of a gas is proportional to the pressure of the gas”

Solg = KHenryPg

Osmotic Pressure

Π = (n/v)RT

R = 0.082057 L · atm / K · mol

C = (n / v) = (mol/L)

T = temperature in Kelvin