## Q2 : Week 9 – 1/16 – 1/20

If you have not already please join the REMIND for this class.

Make Sure the Tums and Aspirin Labs are completed as i will be grading them very soon!

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1/16 – Monday –            Martin Luther King Day – I have a dream that one day this nation will rise up and live out the true meaning of its creed: “We hold these truths to be self-evident, that all men are created equal.”

I have a dream that one day on the red hills of Georgia, the sons of former slaves and the sons of former slave owners will be able to sit down together at the table of brotherhood.

I have a dream that one day even the state of Mississippi, a state sweltering with the heat of injustice, sweltering with the heat of oppression, will be transformed into an oasis of freedom and justice.

I have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their character.

I have a dream today!

I have a dream that one day, down in Alabama, with its vicious racists, with its governor having his lips dripping with the words of “interposition” and “nullification” — one day right there in Alabama little black boys and black girls will be able to join hands with little white boys and white girls as sisters and brothers.

I have a dream today!

1/17 – Tuesday B Day 2, 3b Lab/4

Main focus –

a) To identify the Gas Law Constant needed for KMT equations requires a different                 constant.

b) To Review the concepts of the molar KE and Root Mean Squared Formulas

c) To derive Grahams Law of Diffusion/Effusion

Period 2: – Connected concepts from the form and homework worksheet

1.  Review the Kinetic Molecular Theory worksheet (front page) homework:

Gas Law worksheet 6 – KEY- kinetic energy-grahams law.pdf

a) Review the different R constant needed for KMT equations = JOULES!!!!

b) Implications from the 2 new formulas in terms of Boltzman Distribution graphs/ homework form

2Derive the Graham’s Law of Diffusion or effusion formula.

a) Model the question 1 of side 2 of  the Kinetic Molecular Theory worksheet

2 gases at the same temperature and thus the same Average Molar KE:

KE = 1/2  m µ2

Gas A:         10000 J =  1/2   (2 Kg/mol) (100 m/sec)2

Gas B:          10000 J =  1/2   (200 Kg/mol) (10 m/sec)2

Period 3b/4:

1. Same as above  for 1,2,3-

2.  Lab 19 – Boyles Law Syringes  – Its the error in this lab that will incorporate the kinetic molecular theory                                                        that we are deriving!

LAB 19 – Boyles Syringes Lab.pdf

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Kinetic Molecular GAS law Constant (R) NOTES :

In Kinetic Molecular Equations – (Used to help describe why gases behave according to the ideal

gas law and all of its derived equations:           M = dRT     &     d = PM
P                       RT

Kinetic Molecular Equations are centered around Kinetic Energy formula, KE  = 1/2 mu

and thus are centered around the SI unit of energy = Joule.

Thus our Kinetic Molecular equations must have terms or units that reflect equivalents in Joules.

Remember from experimental evidence PV = nRT or R PV
nT

and we have been using .08206 (atm  L)
(mole K)

as our Gas Law constant (proportionality constant) and you have learned that you must be in same units for your variables as your ideal gas law constant, R otherwise units do not cancel and your calculation will be in error.

In Kinetic Molecular Equations we cannot use this value of
that has uses Pressure (atm) and Volume (V) in its Numerator.

We need a value of R that uses Joules instead in order to reflect the KE that is part of the derived Kinetic Molecular Equations that we derived.
KE per mole = 3/2 RT                                                 Urms              =    √3RT
Molar Average KE                                                  Root Mean Squared Speed             M

This R cannot be the same value as we have been using as it needs to reflect Joules (Energy).

Well fortunately, P x V (the numerator in R) actually can equal Joules if we change the units of

Pressure from atm to Force/Area and Volume from L to meter3 (length x width x height):

Force = mass   x    acceleration due to gravity

Kg      x    meter/sec2

Area =  meter2

P                    x                     V                                  =     Energy
force/area                  length x width x height

Force                x                meter3
meter2

( Kg    x    meter/sec2 )   x   (meter3 ) =   Kg meter2  =    Joule
meter                                                sec2

So with our Kinetic Molecular equations we use R = 8.31      J  _
mol K

This is given in our reference tables: Also because a joule is really a Kg meter2 / sec2 then M must be in Kg!

So after today we now have another gas law equation in our reference tables:
Grahams Law which is really root mean squared: 1/17 – Tuesday’s Homework: –

1. Please complete the second side of the Gas Law worksheet 6 – kinetic energy-grahams law.pdf   worksheet.

2.  Review 1st question with video (if needed) and the key.

*At 19:40 of the lecture posted below I reviewed the first problem on the second side WITH Grahams Law derivation.

Gas Law worksheet 6 – kinetic energy-grahams law.pdf

Gas Law worksheet 6 – KEY- kinetic energy-grahams law.pdf

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2. Back Page – 1st question –  Kinetic Energy – Grahams Law worksheet:

1/18 – Wednesday – A Day – 2/3a Lab, 4

Main focus –

a) To Review Grahams Law of Diffusion (Effusion)

b) To list the Kinetic Molecular Theory requirements for an Ideal gas (student).

Period 2,3a:

1.  Review the 2nd side of the homework, grahams law of effusion

Gas Law worksheet 6 – KEY- kinetic energy-grahams law.pdf

2. Grahams law of effusion / diffusion demos –

a) HCl vs NH3
b) Manometer with He and SF6
c) Demo Graham’s law effusion and diffusion of the 2 balloon in class.Amazing Grace – speed of sound

3.  Real vs Ideal Gas Behavior.

4. Perform Lab 19 – Boyle’s Law Syringes.

LAB 19 – Boyles Syringes Lab.pdf

Period 4:

1.  Review the 2nd side of the homework, grahams law of effusion

2. Grahams law of effusion / diffusion demos –

3.  Real vs. Ideal Gas behavior

Grahams Law of Diffusion of HCl and NH3 Demo:

Grahams Law of Diffusion of HCl and NH3 Demo 2:

Manometer of He and SF6 Demo:

1/18 – Wednesday Homework: –

We are learning about the limitations of the our gas law equations that depend on Ideal Gas behavior.   I started this class for both classes but I did not get far.   Please watch the selected videos  below in the correct order and complete the form.

1.  Please view the Kinetic Molecular Theory – Real vs. Ideal Video from  23:26 – 28:35 only! It starts at 23:26.

2. Please view the Ideal Gas law Limitations with Pressure video from 4:37 – 9:20 only! It starts at 4:37.

3. Please view the Ideal Gas law Limitations with Volume video from 18:44 – 26:10 only! It starts at 18:44.

4. Please view the Real Gas Behavior Demo with a Calculation Video 2:08 – 10:18 only! It starts at 2:08.

5. Complete the Form below.

1. Ideal vs Real Gas: Ideal Gas behavior (assumptions)   View: 23:26 – 28:35 only

2.  Ideal gas limitations with Pressure:  View 4:37 – 9:20 only!

3.  Ideal gas limitations with Volume:  View 18:44 – 26:10 only!

4..  REAL Gas behavior Demo with calculation:  View 2:08 – 10:18 only!

2:  Kinetic Molecular Theory Form with Ideal/Real Gas behavior::

End of Wednesday!

Amazing Grace of He and SF6 Demo:

1/19 – Thursday – B Day 2, 3b Lab/4

Main focus –

a)  To identify that the measured Pressure will be lower than calculated in the Ideal                 Gas Law equation.

b)  To identify that the measured Volume will be higher than calculated in the Ideal                 Gas Law Equation

c)  To Review the Real Errors in Lab 19.  When did the K change the most?

Period 2:

1: Results of our Graham’s Law of Effusion Demo:    2. Kinetic Molecular Theory – Part B – Limitations to the Gas Laws – Real vs. Ideal Student

A) Van der Waals Equation –  An equation created to “fix” the problems with gas law calculations.

1. Pressure is less than what is calculated for in Real Gases

2. Volume is greater than what is calculated for in Real Gases

3. Crush the Can demo – water vapor creating the vacuum!

4. Absolute Zero demonstrator with liquid Nitrogen Demo.

– Calculate the new Pressure using the combined gas law. The calculated result will be greater than the pressure measured due to the Real Gas behavior of the atmospheric gases.

–  N2 (l) – boiling point  =  -196 degrees Celsius or 77 Kelvins.

–  O2 (l) – boiling point =  -183 degrees Celsius or 90 Kelvins. – Clearly the boiling point or the condensation point of oxygen (-183 ° C)  is above the boiling point of nitrogen (-196 ° C). This means that liquid nitrogen is cold enough to condense oxygen to a liquid. If gases condense then they Have REAL significant Intermolecular Attractions.

Period 3b,4:
1. Same as 1 – 4 above

2. Complete Lab 19 –

a) calculate the conversion factor of book per kPa

b) calculate the number of books that will equal to 1 additional 1 atmosphere.

c) calculate the constant for P x V = k (T,n)

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Real Gas Behavior NOTES :  Kinetic Molecular Theory Presentation:

Boyles Law and Real Gas Behavior:

School Bus Demolition:  (school busses acting as REAL GASES!)

1/19 – Thursday Homework: –

Lab 17, 18, and 19 did not have conclusions (initially) but I am asking that you write them and attach them to your labs.

Now the errors in these labs are all based on simple idea that all gases do not behave like the ideal gases. This means that the gases in the labs that we used were placed in formulas that ASSUMED IDEAL GAS BEHAVIOR BUT no gas is completely ideal. This means that there will be some deviation from OUR DERIVED GAS LAWS!!!!  OUR calculations will be off by some amount due to:

1. The gas particles ARE NOT completely random and do not move in straight line motions (actually curved!!)

2.  The collisions are not completely Elastic (they actually stick together a little bit)

3. The gas particles DO ATTRACT each other a little bit.

4. The Gas particles DO HAVE some volume!!!

5. Kinetic Energy is proportionate to Temperature.

1.  Please watch the Real Gas Law demo below to view an example of a calculation of gas pressure that is higher than expected to the above listed NON-Ideal conditions:

2.  Please watch the Gas law Error Review video to apply these errors to your labs.  Write a conclusion for each lab based on the REAL GAS behavior of the gases that were investigated. Attach to your lab and hand in by Monday!

3.  Please complete question 1 only of the Gas law worksheet 8 – Van der Waals.pdf worksheet and review with the key.

Gas law worksheet 8 – Van der Waals.pdf

Gas law worksheet 8 – Van der Waals Key.pdf

One of the Errors in the Lab 19:

Gas Law Lab Error Review:

End of THursday!

1/20 – Friday – A Day – 2/3a Lab, 4

Main focus –

a) To complete Lab 20 – Mg and HCl Stoichiometry

b) To review Gas laws Stoichiometry with manometer, Daltons Law, and Real gas                  behavior through a gas law procedure.

Period 2/3a:

1. Complete Lab 19 –

a) calculate the conversion factor of book per kPa

b) calculate the number of books that will equal to 1 additional 1 atmosphere.

c) calculate the constant for P x V = k (T,n) for each data point.

The comparison of this value will help us determine how Real Gas behavior is affecting our results.

2. Lab 20intro and data collection

3. REAL GAS DEMO – gold fish and liquid Oxygen if time permits.

Period 4:

1Lab 20intro and data collection

2. REAL GAS DEMO – gold fish and liquid Oxygen if time permits.

Crush the Can demo – A Real gas Demo – water vapor condenses in the can that creates a vacuum.

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Lab 20 – The Molar Volume of Hydrogen

Lab 20 – Molar Volume of Hydrogen .pdf

Vapor Pressure of Water table.pdf

Here is the unbalanced chemical reaction (single replacement reaction).

Mg (s)   +    HCl (g)   —>   MgCl2 (aq)    +  H2(g)

Dilute Excess HCl will be added to a Eudiometer tube with a small mass of Magnesium secured by a copper wire.  Only the the Mg will react as only the Mg reacts spontaneous with protons from the HCl OR the proton is a strong enough oxidation agent that can transfer electrons from the metal.  The copper will not react as per the Standard Reaction Potential values posted below:

Cu+2   +     2e-    –>  Cu (s)        0.34 v
2H+     +     2e-    –>  H2 (g)        0.00 v
Mg+2   +    2e-    –>  Mg (s)       -2.37 v

The copper will that will affix the magnesium will not react in the acid and thus all the hydrogen produced will be produced by the oxidation of the Mg metal.

Molar Volume of Hydrogen – Lab 20 –  Calculations:

1/20 – Friday Homework: –

1. Please complete the conclusions for Lab 17, 18 and 19 that are due Monday.

Make sure the TUMS Lab and the Aspirin Lab are completed. I will be grading them this weekend!

2. Complete the Lab 20 calculations to determine the molar volume of hydrogen using the video posted above. Only Period 2/3 Friday is doing this for homework. I will review this Lab before you start the Test.

THERE IS NO Conclusion for this lab.

Today’s Classroom pressure: 752.1 torr

Lab Data  for Halle and Luke: Will do Monday

Volume of gases:

Height of water:

Lab data for Lilly, Fahtima, Maddie, Lucy: Will do Monday

Volume of gases:

Height of water:

3. Complete the Gas Law review form that is posted below. I gave out a hardcopy to complete your work on in class:

Kinetic Molecular Theory Form 3 – Gas Law Review – Google Forms .pdf