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Drill: Name & describe each of
the 7 crystal structures
Drill: Draw LDDs for:
BF3 NH3
BeCl3 C3H6
H3PO4 H2CO3
Drill: Draw LDDs for:
C6H8
Drill: Draw LDD for:
C3H5NO
CHM II
•Test Friday
CHM II HW•Read: Chapter 14
•Work Problems 25 & 29 on page 585
Solutions
Solution•Homogeneous mixture made up of at least one solute dissolved in the solvent
Solute •Substance being dissolved
•Portion in lesser molar amount
Solvent•Substance doing the dissolving
•Portion in greatest molar amount
Colloid•Slightly larger particles
•Light passes & particles stay suspended
Suspension•Even larger particles
•Particles block or reflect light
Tyndall Effect•Because light reflects off suspended particles, the light ray can be seen from the side
Size Comparison•Solution < Colloid
•Colloid < Suspension
Soluble•When one substance (solute) dissolves in another (solvent)
Solubility•The amount of one substance (solute) dissolved in another (solvent)
Concentration•The amount of solute dissolved into solution
ConcentratedSolution
•A solution with a relatively large amount of solute dissolved
Dilute Solution
•A solution with a relatively small amount of solute dissolved
Saturated Solution•A solution with the maximum amount of solute dissolved in the solution
Unsaturated Solution•A solution with less than the maximum amount of solute dissolved in solution
Supersaturated Solution
•A solution with greater than the maximum amount of solute dissolved in solution
Solution Measures•Concentration
–Molarity
–Molality
–Mole Fraction
Percent Solution•Mass of one portion per the total mass, all times 100 %
•%soln = ma/mtotal x 100 %
Drill:•Define & give units for:
–Molarity
–Molality
–Mole Fraction
Molarity•Moles of solute per liter of solution
•M = molessolute/Lsoln
Molality•Moles of solute per kilogram of solvent
•mo = molessolute/kgsolvent
Mole Fraction•Moles of one portion per total number of moles in the solution
•X = molesa/molessoln
Calculate the molarity of a 250 mL solution
containing 5.0 g NaOH dissolved in
water
Calculate the molality of 69 g of C2H5OH dissolved
in 500.0 mL of water
Calculate the mole fraction of each
portion when 92 g of C2H5OH dissolved in
144 mL of water
Drill:•Calculate the mass of KI required to make 250 mL of 0.500 M KI.
Review Drill
Review HW
Calculate the molality & mole fraction of a
solution containing 46 g of C2H5OH
dissolved in 1782 mL of water
Chm II HWProblems: 31 & 38
Page: 585 & 586
AP Chm HWProblems: 31 & 35
Page: 298
Colligative Properties•Properties dependent only on the concentration of particles in solution
Examples•Vapor pressure
•Boiling & Freezing points
•Osmotic pressure
Vapor Pressure•VPsolution = (VPsolvent)(Xsolvent)
•X = mole fraction•VP = vapor pressure
Boiling & Freezing
T = imoKT = change in BP or FP
i = ionic activity
K = BP or FP constant
Osmotic Pressure = iMRT
= osmotic pressure
i = ionic activity
M = Molarity
Calculate the vapor pressure of a solution
containing 150 g C5H10O5 in 162 mL of
water at 30oC
Drill:•Calculate the VP of a solution containing 36 % m/m glucose (C6H12O6) in water at 29oC:
•(VPwater = 30.0 mm Hg)
Calculate BP & FP of 60.0 g of NaOH in
250 mL waterKBP = 0.512oC/moKFP = -1.86oC/mo
Calculate the osmotic pressure of a solution
containing 12 g of NaOH dissolved in 250 mL solution at
27oC
Chm II Homework:Problems: 47 & 87
Page: 585 - 587
AP Chm HW:Problems: 31, 35, & 39
Page: 298
Calculate the vapor pressure of a solution
containing 120 g C3H7OH in 144 mL of
water at its BP.
Drill: Calculate the mass of lead(II)nitrate required to make 250
mL of 0.40 M Pb(NO3)2
Test on Monday on Bonding, Lewis Dot
Diagrams, & Solution Chemistry
Draw LDDs for:BH3 NCl3
CF4 C3H6
SO3 SO3-2
Calculate the osmotic pressure of a solution
containing 12 g of C4H8O4 dissolved in 50.0 mL
solution at 27oC(VP = 26.7 mmHg)
Clausius-Claperon Eq
Hv= R ln(T2)(T1) P2
(T2 – T1) P1
VPbenzene Temp (oC) 24.5 2773.5 127
Calculate Hv for benzene:
Calculate the osmotic pressure of a solution containing 29.9 g of CoBr3 dissolved in
7500 mL solution at 27oC
Calculate the vapor pressure of a solution
containing 12.0 g C3H8O in 14.4 mL of
water at its BP.VPsolvent = 1.0 Atm
Calculate the molality of a
solution that is 33.1 % by mass Pb(NO3)2
in water
Drill: Calculate the osmotic
pressure of 0.88 g of CO2 in 750 mL
of soln at 27oC
AP Test Tomorrow
30.0 g C3H6NF was dissolved in 50.0 g
C6H12O (VP = 20.0 kPa) at 27oC making a 0.800
g/mL solution. Calculate: X, mo, M, , & VP.
180 g C3H8O was dissolved in 180 mL
H2O at 27oC making a 1.5 g/mL solution.
Calculate X, mo, M, , VP, BP, & FP.
A 1.2 g/cm3 aqueous solution is 20.0 % by mass NaOH at 27oC.Calculate: X, mo, M,
, & MP
Calculate the molecular mass of a covalent
compound dissolved in an aqueous solution to make it 25 % by mass when it
boils at 102.048oC
AP Homework:Read: Chapter 11Power Point: 19
Chm II Homework:Read: Chapter 15Power Point: 16