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Q2: Week 8  – 1/10 – 1/14

                                                                                                                                                                        Jump toTuesday,   Wednesday,  Thursday,  Friday                                                                                                                  ______________________________________________________________

1/10 – Monday – A Day – A Day – 2/3a Lab, 4 

Main focus –     

      a) To take a Derivation Quiz

     b) To begin a Molecular Mass Gas law lab

     c) To view gas law relationships through an eggcellent demos.

Period 2/3:  

1. Gas Law Derivation Quiz –

Gas Law Equations Derivation Quiz.pdf
View Download

2. Eggcelllent demos

3.  Lab 18 – Molecular Mass of an unknown gas.

Period 4: 

1. Gas Law Derivation Quiz

2.  Lab 18 – Molecular Mass of an unknown gas.

______________________

Lab 17 – The Molecular Mass of Unknown Gases.

Lab 17 – Molecular Mass of an unknown gas.pdf
View Download
        
2 60 cubic foot tanks of 2 unknown gases are placed on the Lab Cart.  One is more dense than air and one is less dense than air.  The Molecular Mass of each gas will be determined by using our gas laws.
                                             
       1.  Mass out the plastic 1 Liter Erlenmeyer flask with cap (with air).
       2.  Determine the mass of the evacuated Erlenmeyer flask.
       3.  Flush out the flask with unknown holding the flask appropriately to fill it with one of the                              unknown gases and screw the cap tightly.
       4. Mass out the flask with the unknown gas.
       5. Determine the mass of the unknown gas.
       6.  Repeat steps 3, 4, and 5 for the second unknown gas.
       7.  Fill the flask with water and measure the volume of the filled 1 Liter Erlenmeyer flask.
       8.  Measure the temperature of the room and obtain the atmospheric pressure of the day.
       9.  Calculate the Molecular Mass of each gas. 
     10.  Identify the gases based on Molecular Mass.                                                                                                            

 

 ____________________

1/10 – Monday Homework: – 

                                                                                                                                                                               

1:  Please view the lecture on Daltons Law in any speed but take notes on the derivation:                                 
2:  Complete questions 1 and 3 only in the Gas Law worksheet 7 – Daltons Law.pdf worksheet.
       And Review with the key or Lecture below.  
                                                                                                                                                                                                      Gas Law worksheet 7 – Daltons Law.pdf
View Download
                                                                                                                                                                                                  Gas law worksheet 7 – Daltons Law Key.pdf
View Download
                                                                                                                                                                                                        3:  Watch the Daltons Law Demo and Fire syringe demo and complete the form below: 
     You have a total of three submissions tonight for this form.
1:  Daltons Law Derivation
 

 

2:  Daltons Law worksheet question 1 and 3 review video.
 

 

3: Dalton’s Law of Partial Pressure:
 

 

3:  The Fire Syringe Demo.
 

 

 
3:  Daltons Law of Partial Pressure Form::

End of Monday!

                                                                           -.  _________________________________________________________________________________________________________________________

1/11 – Tuesday  – B Day – 2, 3b/4 Lab 

Main focus –                                                                                                                                                         
                                                  

    a) To complete the Molecular Mass calculations of Lab 17

    b) To Review the concepts of Daltons Law and its real life applications

    c) To introduce vapor pressure.

 Period 2: 

1. Lab 17 – review
 
    a) Evaluate Data – Complete calculations and hand in
    b) You may have to redo the gas measurement if really off.
    c) errors
 
2.  Daltons Law of Partial Pressures – 
 
a) Review of Dalton’s law partial pressure demo’s
 
   mole fraction, volumes fraction, pressure fraction are equivalent due to 
 
                                                V = n * K      (Avogadro’s hypothesis)
 
b) Review of Homework:                                                                                                                                                             
Gas law worksheet 7 – Daltons Law Key.pdf
View Download
 
c) partial pressure ideas
      Scuba Tanks, Brooklyn Bridge, and the Romans (lung demo)

                                                                                                                                                                                                       Period 3/4: 

1. Same as period 1 – Include demo with nitric acid – 
More time spent on Vapor Pressure ideas.

                                                                                                                                                  

Daltons Law Applications:

Nitric Acid and Copper demo with gas law implications.
 

 

Today’s Class lecture.
 

 

____________________

1/11 – Tuesday Homework: –                                                                                                                                                                                                                           

1. Please complete the following worksheet AND review with the key.
 
 *Remember what is proportionate when gases are in the same container!
           
Daltons Law Worksheet 2.pdf
View Download
 
Daltons Law Worksheet 2 Key.pdf
View Download

                                                

 _____________________________________________________________________________________________________________________

1/12 – Wednesday – A Day – A Day – 2/3a Lab, 4 

Main focus –                                                                                                                                                         
                                                  

    a) To Review an advanced AP Daltons Law Problem

    b) To identify the strength of IMF in different liquids based on their vapor pressure

    c) To define boiling, vapor pressure and distillation

Period 2/3:  

 

  1. Review of Homework:   

          Daltons Law Worksheet 2 Key.pdf
          View Download
 
   2. Complete partial pressure ideas
         Scuba Tanks, Brooklyn Bridge, and the Romans (lung demo).   
   
   3. Vapor Pressure intro, table H – 
 
      a) boiling cold in a baggie
      b) liquid nitrogen with an air horn
                                                                                         

    4.   Lab 17 complete/ Lab 18 – Molecular Mass of quadrupled distilled Butane – intro

Lab 18 – Molecular Mass of quadrupled distilled Butane
 
Lab 18 – Purity of Butane – water displacement.pdf
View Download
 
Vapor Pressure of Water table.pdf
View Download

Period 4: 

1. Review of Homework

3. Vapor pressure intro/ table H                                                                                                                                                            

 

______________________

NOTES FOR Vapor Pressure:

 Vapor pressure – slide 8 – 17 in Pressure Intro Presentation – posted at the end of today’s post.
 
Vapor Pressure is the Force per Area (F/A) created by gas molecules that have just evaporated from the liquid state.  This pressure of evaporating liquids depends on how well the molecules of the liquid attract each other.  These attractions are called IMF’s (Intermolecular Forces or Attraction).  

 The stronger the IMF between the molecules in the liquid the MORE that the liquid Resists evaporation AND THUS will evaporate less (at the same temperature) and thus produce LESS vapor pressure.
The strength of the IMF’s are unique for each liquid and thus each liquid has a unique vapor pressure curve.

Another important FACTOR in vapor pressure is the Temperature of the the liquid.  Even though each liquid has its own vapor pressure due to its unique strength of IMF’s, ALL LIQUIDS will increase their vapor pressure or evaporating due to an INCREASE in Temperature!!
An increase in Temperature is a result of an increase of energy that is absorbed AND will be used to free molecules from each other by breaking IMF’s.

*IMF’s ARE NOT BONDS!

All liquids have a unique vapor pressure curve based on how strong or weak they ATTRACT each other.  
Example:  Propanone does not H-bond with itself but water does.  Water has Stronger IMF than propanone.
 
All liquids will increase their vapor pressure with an increase in Temperature.
Example:  Water has a lower vapor pressure than Propanone at the same temperature but they will both increase when temperature increases as IMF’s are broken.
 
Vapor pressure values will increase with increase of temperature 
until the vapor pressure EQUALs the Atmospheric pressure!
I like to think of boiling as the temperature which a liquid reached MAX EVAPORATION at a certain atmospheric Pressure.  What limits this temperature OR BOILING IS THE Atmospheric Pressure.  This means that every liquid can boil theoretically at any temperature!  If you look back at Table H, water can boil at 55 degrees Celsius if the Atmospheric pressure is 10 kPa (about .1 atm).  Lowering the atmospheric pressure will affect the boiling pint because you will need less vapor pressure to Equal or match the lowered atmospheric pressure.  Water will also boil at about 105 degrees when the atmospheric pressure is raised to 120 kPa (about 1.2 atm).  To combat this will usually talk about boiling in terms of STANDARD PRESSURE = 101.3 kPa or 1 atm or 760 torr or 14.7 psi.  In Table H above the horizontal line going across is the STANDARD atmospheric Pressure, thus when the vapor pressure of any liquid reached that line at standard pressure the temperature of the this boiling point is the NORMAL BOILING POINT. We compare liquids Normal Boiling points!
 
                Larger Normal Boiling Point    = Higher IMF’s = Lower Vapor Pressure                   WATER
            Smaller Normal Boiling Point   = Lower IMF’s = Higher Vapor Pressure             PROPANONE
 
Distillation of Coke Demo:
 

  A mixture (2 or more substances that are not Bonded together) can be separated physically.  A physical separation is one that breaks attractive forces AND NOT CHEMICAL BONDs.  

In this demo the water in the Coke mixture retains its unique boiling point because it Is NOT BONDED with any other component.  It will reach its maximum vapor pressure (boiling point) at different temperatures than the other components (because water has unique strength of attractive forces that results in a unique vapor pressure) thus water will leave as a gas and then cool to condense into a liquid as its distilled. 

 

I use distilled water for all of my solutions that I make for all of the demos and labs. WHY?
 
Crude oil Refinery:

This is picture of a gasoline refinery that you can see in New Jersey as you travel south on the New Jersey Turnpike.

This is an example of  Fractional Distillation of Crude oil. Like all Distillation it is based on the different boiling points/vapor pressures of the mixtures of liquids that are being separated.

Notice the tubes coming off the columns at different heights. This demonstrates the condensation of the vapors at different temperatures.  The higher the gas needs to travel to cool and condense into a liquid the weaker the IMF’s of the liquid in the mixture and the high its vapor pressure.

Remember that boiling temperature (point) is equal to the condensation temperature.

Compounds at that are gases at room temperature are Gases because they have weak attractive forces between them AND THUS they would boil at very low temperatures.  
 
They are gases because they have already BOILED!!!! AND THUS they have extremely high vapor pressures!  And thus they must have low NORMAL boiling points because their very high vapor pressures will equal the atmospheric pressure at low temperatures.
 
So gases have:
 
                              1 ) very weak IMF’s (which make the molecules evaporate easier!)
 
                              2) High vapor pressure (due to the ease in which molecules evaporate)
 
                              3) Low Boiling points (due to the high vapor pressure that reaches atmospheric                                                 pressure  quickly).
 
Here is a great example.  Nitrogen liquid boils at – 196 degrees Celsius and thus has already boiled and exits as a gas in our atmosphere.  Below I have liquid Nitrogen, N2 (l) which was made by pressurizing Air into a liquid (forcing the nitrogen molecules to attract each other).    
     
Lets add liquid nitrogen to table H and see where it fits!!!
How does liquid nitrogen (red) compare to the other liquids???????

Vapor Pressure Demo:
 

 

Vapor Pressure Demo 2:
 

 

Liquid Smear demo:
 

 

Air Horn Destroyed by Temperature: Pressure is proportionate to Temperature :                Gay-Lussacs Law OR the vapor pressure of the can is decreased!!!!!!

 

 

Butane – boiling cold demo –

 

 

 ______________________

1/12 – Wednesday Homework: – 

                                                                                                                                                                                                                               
1.  Complete questions of 4 and 2 only in the Gas Law worksheet 7 – Daltons Law.pdf worksheet.
      Please do question 4 first and then question 2! This question will connect with Lab 18!!!!
       
2. Review with the key or use the video posted below.                                                                                                     
Gas Law worksheet 7 – Daltons Law.pdf
View Download
                                                                                                                                                                                                    Gas law worksheet 7 – Daltons Law Key.pdf
View Download
 

2. Question 4 and 2 Reviewed:

 

 

_________________________________________________________________________________________________________________________

1/13 – Thursday – B Day – B Day – 2, 3b/4 Lab 

Main focus –                                                                                                                                                         
                                                  

    a) To incorporate vapor pressure into Dalton’s law problems

    b) To determine the Molecular Mass of Butane by water displacement

Period 2:  – 

1.  Collect Lab 17. 

2.  Boltzman distribution of kinetic energy with vapor pressure

3Lab 18 data collection.

Period 4:  – 

1.  Complete the Vapor Pressure lesson

a) IMF’s are weaker than chemical bonds – asphalt

b) Boltzman Distribution of Kinetic Energy for vapor pressure

c) Distillation

d) boiling cold demo/baggie with quadruple distilled butane

2.   Lab 18 data collection.

                                                                                                          

Boiling cold water in a Vacuum chamber: Notice the temperature changes! Evaporation or boiling is an endothermic process due to the high energy molecules leaving the system.

 

 

______________________

Lab 18 – The Molecular Mass of Quadrupled Distilled Butane by                                                                  water displacement.

Lab 18 – Purity of Butane – water displacement.pdf
View Download

        
 * make sure students do not invert the can to get the gas as it will dispense liquid that will add to the mass lost but not add significantly to the volume. (liquids have a MUCH smaller volume that a gas)
 
Vapor Pressure of Water table.pdf
View Download 
 
A can of quadrupled distilled butane (by fractional distillation) will be collected by water displacement.  The mass of the butane will be determined by the difference of the mass before and after dispensing the gas.             
       
Butane,  C4H10 will not dissolve or react with water and thus is an appropriate candidate for water displacement.  The volume will be measured using a eudiometer tube and the total pressure will INCLUDE water vapor as water has a vapor pressure at all temperatures.
     
Molecular Mass of Butane Lab calculations explained:      
                                                                                                                 

Live Stream of the lab (last year):

 

_____________________

1/13 – Thursday Homework: – 

                                                                                                                                                                                                                               
1. Please view the Vapor Pressure Lecture below.   

2.  Complete the Vapor Pressure Form.                                                                                                

1. Vapor Pressure Lecture:

 

 

 
2:  Vapor Pressure Form::

End of Thursday!

_________________________________________________________________________________________________________________________

1/14 – Friday – A Day – A Day – 2/3a Lab, 4 

Main focus –                                                                                                                                                         
                                                  

    a) To Perform Lab 18 – Molecular mass of the quadupled refined butane.

a) To compare and contrast phase diagrams of water and carbon dioxide.

 

Period 2:  – 

1.  Perform Lab 18 – water displacement. 

2.  Limitations to Lab 18

a) How to avoid the manometer part!

b) water displacement limitations

3.  Vapor pressure to Phase Diagrams, refrigerators, air conditioners (did not quite get to this)

Phase diagram review:

             a) Critical Point
             b) water vs. carbon dioxide
             c) Freeze dried / astronaut food
              d) ICE SKATING/ the titanic

 

Period 4:  – 

1.  Complete Lab 18 calculations

2.  Limitations to Lab 18

a) How to avoid the manometer part!

b) water displacement limitations

3. Vapor pressure to Phase Diagrams, refrigerators, air conditioners –(did not quite get to this)

Phase diagram review:

             a) Critical Point
             b) water vs. carbon dioxide
             c) Freeze dried / astronaut food
              d) ICE SKATING/ the titanic

Water Phase Diagram:

Comparison or water to carbon dioxide:

 

 

 

 

Use Phase Diagram lesson:

______________________

Lab 18 – The Molecular Mass of Quadrupled Distilled Butane by                                                                  water displacement.

Lab 18 – Purity of Butane – water displacement.pdf
View Download

        
Vapor Pressure of Water table.pdf
View Download 
 
 * make sure students do not invert the can to get the gas as it will dispense liquid that will add to the mass lost but not add significantly to the volume. (liquids have a MUCH smaller volume that a gas) 
 
A can of quadrupled distilled butane (by fractional distillation) will be collected by water displacement.  The mass of the butane will be determined by the difference of the mass before and after dispensing the gas.             
       
Butane,  C4H10 will not dissolve or react with water and thus is an appropriate candidate for water displacement.  The volume will be measured using a eudiometer tube and the total pressure will INCLUDE water vapor as water has a vapor pressure at all temperatures.
     
Molecular Mass of Butane Lab calculations explained:      
                                                                                                                 

Live Stream of the lab (last year):

 

_____________________

1/14 – Weekend Homework: – 

                                                                                                                                                                                                                               
1:  Please complete the Gas Law Stiochiometry 2015.pdf worksheet and review with the key.
Think about how we solved the homework Tuesday night using Dalton’s Law of Partial Pressure and the manometer (column of water).                 
       
Gas Law Stoichiometry 2015.pdf
View Download
 
Gas Law Stoichiometry key p.pdf
View Download

 

2: Complete Phase diagram worksheet  and review the answers with the key that is on the same worksheet.  You will probably need to review the concept with the phase diagram worksheet i have posted a lecture below:
 
Solutions 1a – phase diagrams.pdf
View Download

 

                                                                                                                                                    

2. Phase Diagram Lecture:

 

End of week 8!