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Today…Get Out:
Nothing
Our Plan:Airbag Lab (Reading & Initial Measurements)
Homework (Write in Planner):Nothing
Today… Get Out:
Goggles, Lab Handout, Bag of Supplies
Our Plan: Airbag Lab
Quick Reminders: Come up with a design FIRST (use 2.50 g of baking soda and
29.8 mL of vinegar for each trial). Make sure to time the reaction from beginning to end AND
measure the height of your bag for EVERY TRIAL! After you have a design that you like, tinker with the amounts
of vinegar and baking soda until you have the perfect combination.
You MUST have a design by the end of class!
Homework (Write in Planner): Nothing
Today… Turn in:
Nothing Our Plan:
Airbag Lab – Packet due TODAY! Must Have:
Calculations p. 3 & 4 Trial(s) with Speed & Height/Diagram p. 5 At least 6 trials changing amount of chemical
Final Tests the last 20 minutes Homework (Write in Planner):
Enjoy your Weekend
Check this out…
Oobleck http://www.youtube.com/watch?v=1
nX8jvj_jOk
Today… Turn in:
YOU NEED YOUR TEXTBOOK TODAY AND NEXT CLASS!
Our Plan:Video ClipsStop the Process Reading & Activities
Homework (Write in Planner):Finish AT LEAST the first two
pages from the packet (2 & 3).
Here’s some of what you’ll learn…
http://www.youtube.com/watch?v=PBF_t8Zt9AU
Page 4, box #1
http://vimeo.com/2670546
Today… Turn in:
YOU NEED A TEXTBOOK TODAY! Get out Stop the Process & Clicker
Our Plan: Clicker Review Immiscible Love Story Set Up Borax with your table group Finish Stop the Process Reading Quick Review of Saturation Supersaturated Lab Wrap Up – Mix-Pair-Share
Homework (Write in Planner): Finish Stop the Process
Quick Review – Grab a Clicker In salt water what is the solute, salt or
water? In lemonade what is the solvent,
water, lemon juice, or sugar? Which kind of Kool Aid has the MOST
SOLVENT; very sweet or barely sweet?
What do we call a solution that can conduct electricity?
Solution Formation Animation
http://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/molvie1.swf
Immiscible Love Story
Steve Spangler Video – Stop the Process Last Box
http://www.stevespanglerscience.com/experiment/instant-hot-ice
Saturated vs. Unsaturated
Video Clip of Supersaturation – Hot Ice
Lab Time!
Wrap Up – Mix-Pair-Share
1. How can you tell if a solution is saturated, unsaturated, or supersatured?
2. What do you add to a solution to make it supersaturated?
3. What is an example of two things that are immiscible?
4. What does it mean if something is deliquescent?
5. In Jello, what is the solute and what is the solvent?
Today… Turn in:
Stop the Process Our Plan:
ReviewFinish Supersaturated LabMolarity POGILWrap Up – High Five
Homework (Write in Planner):Finish POGIL
Review– Mix-Pair-Share
1. How can you tell if a solution is saturated, unsaturated, or supersatured?
2. What do you add to a solution to make it supersaturated?
3. What is an example of two things that are immiscible?
4. What does it mean if something is deliquescent?
5. In Jello, what is the solute and what is the solvent?
Wrap Up
As a team, what are 5 things that you learned today?
Saturated vs. Unsaturated
Today… Turn in:
Get Out Index Card/Sticky Note and number 1 - 8
Our Plan:Molarity Quick ReviewMolarity QuizFinish POGILStart Crossword Puzzle, if time
Homework (Write in Planner):POGIL, if not finished
Vocab Review
Which word from the word wall am I?1. When you add water to Kool-Aid and make it
less concentrated.2. Two substances that can’t mix, like oil and
water.3. Milk, cheese, fog, mayonnaise4. If you add a seed crystal and a solution
crystallizes.5. In ocean water, water is the _____.6. A substance that cannot conduct electricity.
Molarity Review
M = mol/L
7.What is the molarity of a solution with 3.4 grams of HCl in 157 mL? (0.59 M)8.What volume of solution would be made from 2.1 moles of 3.72 M solution? (0.56 L)
Today… Turn in:
Get out POGIL Our Plan:
Finish POGILMolarity Activity
Homework (Write in Planner):POGIL Due next classState Assessment Next Class
Today… Turn in:
Nothing Our Plan:
State AssessmentMolarity Review ActivityMolarity Quiz
Homework (Write in Planner):Nothing
Today… Turn in:
POGIL & Grab a Clicker Our Plan:
Vocab Crossword Puzzle (25 min)Dilution NotesRainbow in the Blue LabClicker Review
Homework (Write in Planner):Finish Lab Questions & Crossword
Review Time
Clicker Review
What volume of solution would be made if you have 78.9 g of HCl and want to make a 3.72 M solution?
What is the percent by mass of a 25.6 g Kool Aid solution with 3.87 g of Kool Aid powder?
Dilution
Definition- making a solution less concentrated
Equation – M1V1=M2V2
where M= molarity & V=volume
Example
What volume of concentrated HCl (12.4M)should be used to make 250mL of 4M HCl?
Example
What volume of water should be used ?
Making 250mL
Example 2 12mL of an unknown
concentration of sulfuric acid was used to make a 500mL sample of 0.56M sulfuric acid. What was the concentration of the unknown?
Stop!Complete the example problems in your notebooklet.
LAB TIME!!!
Complete the rainbow out of the blue lab
Wrap Up
Clicker Review 2 Clicker Review 3
Today… Turn in:
Crossword Puzzle - basket Dilution Lab - basket
Our Plan: Clicker Review Daily Challenge Notes Worksheet #2
Homework (Write in Planner): Worksheet Due next class
Daily Challenge
In the winter when the streets are going to become icy, what does the city do? Why do they do it?
Colligative Properties
Molality
Concentration of a solution expressed as moles of solute per kilogram of solvent (m)
Equation
m= moles solute mass of solvent (kg)
Example
A solution was prepared by dissolving 17.1g of sucrose in 125g of water . Find the molal concentration of this solution.
m= moles solute mass of solvent (kg)
Example continued …
Find moles of solute- 17.1 g sucrose x 1mole = 0.0500 mole
342.34 g Find kg solvent – 125g x 1kg = 0.125kg
1000g Use equation- 0.0500 mole = 0.400 m
0.125kg
Try It Out
Do #1 & #2 on your worksheet
Colligative Property
Properties that change when solute particles are added.
Vapor Pressure Lowering
Vapor Pressure is the pressure caused by molecules that have escaped from the liquid phase to the gaseous phase.
It is the tendency of molecules to evaporate.
Vapor Pressure Lowering
Liquid molecules at the surface of a liquid can escape to the gas phase when they have enough energy.
By adding a solute the amount of surface area for the escaping solvent molecules is less (solute particles take up space).
The solvent molecules have a lower probability to evaporate (pressure is lower)
Vapor Pressure LoweringExample – water vs. salt water
Freezing Point Depression
In order for a liquid to freeze it must form crystals.
When a solute is added, it disrupts the solution’s ability to form crystals.
Freezing Point Depression
Example – Putting salt on icy sidewalks in the winter
Another Example
Antifreeze in carsInsects & Reptiles– survive
freezing temps by producing a form of antifreeze (alcohols and sugars)
Species of fish in the Antarctic
Freezing Point Depression
The Equation
Δtf = Kfm
Δtf (freezing point depression) is the difference between the freezing points of the pure solvent and a solution
Kf is the molal freezing point constant m is the molality
Boiling Point Elevation
Because the vapor pressure is lower, it takes a higher temperature to boil a solvent.
Boiling Point Elevation
Adding salt to water when making pasta?NO! Would take 1.3 lb of salt to raise temperature 2 degrees
Boiling Point Elevation
Example – antifreeze in a car’s radiatorServes as a coolant in the summers that keeps it from “boil overs”.
Boiling Point Elevation
The Equation
Δtb = Kbm Δtb (boiling point elevation) is the
difference between the boiling points of the pure solvent and a solution
Kb is the molal boiling point constant m is the molality
Colligative Sample Problem 1
What is the freezing-point depression of water in a solution of 0.0500 mol of sucrose (C12H22O11), and 200 g of water?
Problem 1
Δtf = Kfm
Δtf = ?Kf = -1.86 ○C/m (packet)m = mol solute/kg solvent
= 0.0500 mol/0.2 kg
= 0.3 m
Problem 1
Δtf = Kfm
X = (-1.86 ○C/m)(0.3 m)
X = -0.6 ○C
Colligative Sample Problem 2
A water solution containing an unknown quantity of solute is found to have a freezing point of -0.23 ○C. What is the molal concentration of the solution?
Problem 2
Δtf = Kfm
Δtf = -0.23○C – 0○C = -0.23○C
Kf = -1.86 ○C/m (packet)m = x
Problem 2Δtf = Kfm
-0.23○C = -1.86○C/m(x)
-0.23○C = x-1.86○C/m
X = 0.12 m
Colligative Sample Problem 3
What is the boiling-point elevation of a solution made from 20.0 g of a solute and 400 g of water? The molar mass of the solute is 62.0 g.
Problem 3
Δtb = Kbm
Δtb = x
Kb = 0.51○C/m (packet)m = moles solute/kg solvent
Problem 3 Need to find moles solute:
20.0 g x 1 mole = 0.323 moles 62 g
m = 0.323 moles/0.4 kg m = 0.8
Problem 3
Δtb = Kbm
Δtb = x
Kb = 0.51○C/m (packet)m = 0.8
Problem 3
Δtb = Kbm
X = (0.51○C/m)(0.8 m)
X = 0.4 ○C
Homework
Complete the Colligative Properties WS for homework!
Lets do 6a together
LAB TIME!
Complete the Freezing Point Depression Lab.
Wrap Up Clicker Review
Today… Turn in:
Get WS #2 out to check Our Plan:
Quiz, Quiz Trade Molality Quiz Colligative Lab Salting Roads Reading Test Review
Homework (Write in Planner): Test Review due next class TEST NEXT CLASS
Review Answers
V1 V2 V3 V4#1 15.3 m 7.35 m 250.0 m 24.4 m
#2 -0.033 °C -0.925 °C -0.895 °C -1.66 °C
Wrap Up
Clicker Review #3 Clicker Review #4
Today… Turn in:
Get out Test Review to Check Our Plan:
Worksheet Race Go over Test Review Unit 10 Test
Homework (Write in Planner):