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  Q1 : Week 9  – 10/24 – 10/28

                                                                                                                                                                           Jump to:   Tuesday, Wednesday, Thursday, Friday 

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If you have not already please join the REMIND for this class.                                                                                                                                                                                                                             
________________________________________________________________________________
 10/24 – Monday – A Day – 2, 3a Lab/4                                    Jump to:  Monday Homework

Main focus –     

a) To demonstrate a limiting reagent demo – Flaming tube demo

b) To review the stoichiometry of how to determine the Limiting Reagent and the Excess Chemical.

c) To review the Stoichiometry Table in limiting reagent problems 

d) To complete the hydrogen balloon analysis.

   

Period 2/3a: 

1. Hydrogen Balloon Demo – In LGI  – Which ratio of gases will give us the best cake?

2.  Flaming Flask demo with cyclohexane –

3. Conservation of Mass presentation – did not get to 

4. Flaming Tube Demo – 

a) Which reactant was Limiting the reaction?

c) Calculate the Limiting reagent given the worksheet from homework of the weekend.

d) Use the chart method (Stoichiometry table) to solve the same problem and “see” the ratios.

e)  Determine the Limiting Reagent and Excess chemical from the worksheet from this weekend.
 

Limiting reagent intro demo new worksheet.pdf

 

5)  Determine the Limiting Reagent and Excess from the Stoichiometry 3 – ICE Table Molarity Salsa.pdf  worksheet using the “chart method”

Stoichiometry 3 – ICE Table Molarity Salsa.pdf
View Download
 
Stoichiometry 3 – ICE Table Molarity Salsa key BEST p.pdf
View Download

Period 4: 

1. Video analysis of the Balloon Explosions from Friday

2. Conservation of mass presentation – did not get to 

3. Flaming Tube Demo- chart method review. 

 

 

Conservation of Mass Presentation: applications of balancing chemical reactions 

1 : Period 2’s Hydrogen balloon analysis –

 

1 : Period 4’s Hydrogen balloon analysis –

 

 _____________________________________________________

10/24 – Monday’s Homework: – 

1. Complete the backside of the Limiting reagent intro demo new worksheet.pdf (questions 3 and 4 ONLY) that was homework (front side) from this weekend, using the video posted below.  You could try these 2 questions on your own first and then view the video if you are feeling adventurous!

Limiting reagent intro demo new worksheet.pdf with the video posted below.  Start the video at 16:26 as you are not held accountable to questions 1 and 2 yet. We will be using the concept of limiting reagent in different type of AP Multiple Choice Problems. 
 
Back side (questions 3 and 4) of the following worksheet:
Limiting reagent intro demo new worksheet.pdf

2. Complete the Short Form from a Tall Teacher below:  This form is based on a recent free response question. You have 3 submissions to this form. Use the ICE Chart! 

Limiting Reagent Google Form – handout.pdf

1 : Side 2 of Friday’s homework –  Teaches the chart method!

 

 
2: Limiting Reagent Form – A short form 
  

 

_______________________________________________________________                                                         Jump to:  Tuesday Homework

10/25 – Tuesday – B Day – 2, 3b Lab/4                                            

Main focus –                                                                                                                                                         
                                                   

a) To Review the ICE table method of determining the limiting reagent.

b) To perform or take notes on a precipitation analysis lab.

c) To begin the conservation of mass presentation – balancing chemical reactions,                                           Stoichiometry  of  chemical reactions using the mole ratios that we get from balancing 

 

Period 2 –  

* Quick look at yesterdays hydrogens explosions using video below.

1.  We will review the Limiting Reagent Form 1 with the key below:

Limiting Reagent Form 2021 – Google Forms key.pdf                                                                                                View Download

 

2. Determine the Limiting Reagent and Excess from the Stoichiometry 3 – ICE Table Molarity Salsa.pdf  worksheet using the “chart method”

We determined the Limiting Reagent, excess (and how much), and the amount of product Using the chart method after writing the long hand method that was first taught Last Thursday night.

Last Thursday (without the Chart method) :

Stoichiometry 3 – Molarity limiting reagent.pdf
View Download
 
Stoichiometry 3 – Molarity limiting reagent Key.pdf
View Download

 

Last Friday with the chart method on the second side:

Stoichiometry 3 – ICE Table Molarity Salsa.pdf
View Download
 
Stoichiometry 3 – ICE Table Molarity Salsa key BEST p.pdf
View Download

Today (in class and live ) I will model the 1st side with the chart method and particulate diagram of ions

 Stoichiometry 3 – ICE TABLE (side 2) – Molarity limiting reagent  p.pdf

 

Period 3b/4 –* Quick look at yesterdays hydrogens explosions using video below.      

1.  Same as 1 and 2 above. 

2. Conservation of Mass presentation – complete – 

100% Hydrogen balloon was the Hindenburg

 2 : 1 ratio balloon was the The Challenger.          

                                                                                                                   

______________________

3b/4  Lab – Lab 8 – Precipitation Analysis of an Alkali carbonate 

1. Lab 8 – Identify the alkali in the original salt of a metal carbonate.  
                                                                                                                                                                                                                                Lab 8 – Gravimetric analysis of a metal carbonate NEW 1920.pdf
View Download
 
     Data gathering for Lab 8 –
     Measure your data from Lab 8 – Gravimetric analysis of a metal carbonate.
    a) dry out carbonates with microwave.
    b) attain dried mass of unknown carbonate.
    c) Dissolve in water (about 200ml)
    d) Add 125 ml CaCl2
    e) filter precipitate with aspirator and Buchner funnel.
    f) dry out precipitate (put measured filter paper on watch glass) in oven.                                                                   

1 : Period 2’s Hydrogen balloon analysis –

 

Conservation of Mass Presentation: applications of balancing chemical reactions 

_____________________________________________________

10/25 – Tuesday’s Homework: –

1.  Please complete the Title page, Background, Objectives, Materials procedure, and DATA section for Lab 7 on the shared google that I have SHARED WITH YOU. If you complete this on your own google doc then I will have no access when I grade!                                                                                                                                                                                                                                

2:  Please complete – Stoichiometry 4 – Precipitation – limiting reagent .pdf side one with me with the video below and then complete the side 2 with the key or with second video.

 
Stoichiometry 4 – Precipitation – limiting reagent .pdf
View Download
                                                                                                                                                                                        Stoichiometry 4 – Precipitation – limiting reagent Key p.pdf
View Download

                               

2 : Stoichiometry 4 – Precipitation – limiting reagent – side one tutorial.

2 : Stoichiometry 4 – Precipitation – limiting reagent – side 2 tutorial.

 

 _________________________________________________________________________                                     Jump to:  Wednesday Homework

10/26 – Wednesday – A Day – 2, 3a Lab/4                                 

Main focus –          
 
a)  To perform a precipitation analysis laboratory assignment – To determine the moles of a dissolved salt by precipitating out an ion from that salt.
 

Period 2, 3a – 

1.  Conservation of Mass Presentation – Challenger & Hindenburg

        100% Hydrogen balloon was the Hindenburg

         2 : 1 ratio balloon was the The Challenger.       

 

2.  Take notes on  Lab 8 – Precipitation Analysis – notes and begin. 

      Lab 8 – Gravimetric Analysis of a Metal Carbonate – (precipitation analysis) – 
                   Introduction to lab. Identifying unknown through g/mol. 
     a) Discussion of Bernoulli’s principle in explaining how the aspirator works. 

               

3.  Run Lab 7  – isolate the precipitate and place in oven

Period 4 – 

1.  Take notes on  Lab 8 – Precipitation Analysis – notes and begin. 

      Lab 8 – Gravimetric Analysis of a Metal Carbonate – (precipitation analysis) – 
                   Introduction to lab. Identifying unknown through g/mol. 
     a) Discussion of Bernoulli’s principle in explaining how the aspirator works. 

               

2.  Run Lab 7  – isolate the precipitate and place in oven

 
                                                                                                                       

Conservation of Mass Presentation: applications of balancing chemical reactions 

______________________

   Lab 8 – Precipitation Analysis of an Alkali carbonate 

1. Lab 8 – Identify the alkali in the original salt of a metal carbonate. 
This a precipitation analysis lab where we are identifying the metal salt through the mole ratios of the precipitate. The original salt is either:   Li2CO3  or  Na2CO3  or  K2CO3.
  
You will identify the original salt by calculating its formula mass through precipitation analysis.
                                                                                                                                                                                  Lab 8 – Gravimetric analysis of a metal carbonate NEW 1920.pdf
View Download                                                                                                                                                                                                          
Data gathering for Lab:
    a) dry out carbonates with microwave.
    b) attain dried mass of unknown carbonate.
    c) Dissolve in water (about 200ml)
    d) Add 125 ml CaCl2
    e) filter precipitate with aspirator and Buchner funnel.
    f) dry out precipitate (put measured filter paper on watch glass) in oven.                                                                                       

Calculations:  

        A.  TAKE out the precipitate (calcium carbonate) and carefully mass out the filter paper and  
               precipitate.  DO NOT MASS OUT THE WATCH GLASS.
 
        B. Calculate the moles calcium carbonate – Use stoichiometry to relate the moles of the precipitate to   
              the moles of the original salt (unknown metal carbonate).
 
        C.  Calculate the Molecular Mass/Formula Mass of the salt now that we know the grams of the  
              original dried salt (that was measured in the beginning after it was microwaved) and the moles of   
              the original salt that was determined above.
 
        D.   Determine the unknown formula of the salt given that the metal in the salt could only be   
              Li,  Na, or K. Remember that your experimental value will be greater than the molecular/formula   
               masses of the known salts because the moles determines from the experiment are undervalued.
 
        E.  Determine the theoretical mass of the precipitate (calcium carbonate) that would be      
              produced using the step E and F above. Show all work!
 
        F.  Calculate the percent yield and percent error using the theoretical value above.
 
        G.  Complete the diagram on the bottom of the second page that illustrates all compounds in   
              the solution before you filtered out the precipitate.                                                                                                                                                              

Lab 8 introduction – A review of the basic premise of this precipitation analysis lab

 

______________________________________________

10/26 – Wednesday Homework: –

1.  Please complete the Data, Calculations, and Results page of Lab 7 on the Google doc that I shared with you.  Guidelines are posted under Last Friday.

2.  Please view the Lab 8 – review video below.

3. Complete the form based on Lab 8’s calculations.  Today in class you filtered the precipitate unto a known mass of filter paper.  I am drying your samples now in the oven.  Tomorrow you will subtract the dry mass of your filter paper to get the dry amount of calcium carbonate (chalk!). IN the FORM BELOW WE ARE PRETENDING that we are doing the same lab and will follow the same steps as we did today (with given values of mass of your unknown salt and filter paper).  IF you need to please review these calculations with the video below.

2 :Lab 8 review –  This might help with your calculations and tonights form!

 

 3: Gravimetric Analysis Lab  –  

 

                                                                                                                                                                                                                                                      Jump to:  Thursday Homework
_______________________________________________________________________________________________________________________________________

10/27 – Thursday – B Day – 2, 3b Lab/4                                                                     

Main focus –     
                                                                                                                                               

a) To complete all calculations of Lab 8 and the error analysis.

b) To perform the analysis of carbonates (Lab 9 ).

c) To demonstrate Bernoulli’s principle (explanation of the aspirator in vacuum filtration).

                                                                                                                                                               

Period 2 – 

1.  Complete the data collections of Lab 8 – Our precipitate (CaCO3) is in the oven.

2.  Complete the calculations of Lab 8.   

3.  Identification of Sample A or B – Visual identification of the salts, Q and A of the Lab. 

4.  Begin Take-home quiz.      

Period 3b, 4 – 

1.  Identification of Sample A or B – Visual identification of the salts, Q and A of the Lab. 

2.  Bernoulli’s principle demos – Discussion of Bernoulli’s principle in explaining how the aspirator                                                                    works.         

3.  Lab 9 – Analysis of Carbonates, lab set-up and data collection.   

4.  Begin Take-home quiz.         

                                                                                                 

.______________________

Lab 9 – Analysis of Sodium Carbonate and Sodium Hydrogen Carbonate 

Lab 9 – Determine the identity of the carbonate by reacting the 2 salts with HCl to produce NaCl.  How much NaCl is made will determine the identity of the salt.   
 
           The salts are either:          Na2CO3     –   sodium carbonate –  washing soda   
                                                              NaHCO3    –   sodium hydrogen carbonate –  baking soda                                                                                                                                                                                                                      This a NOT a precipitation analysis lab but it an Analytical Lab as we will use stoichiometry to identify the starting salts by using how much NaCl is produced by reacting them with HCl.                                                                                                                                                
LAB 9 – Unknown carbonates Lab.pdf
View Download
 
Data gathering for Lab:
      a) mass out unknown carbonates A or B in an evaporating dish
     b) add excess HCl till the reaction reaches completion.
     c) place the evaporating dish on a hot plate under the fume hood (evaporating off the water to                        recover NaCl)
   

______________________

10/27 – Thursday Homework: – 

1.  Please complete the Data and Calculations of Lab 8 – due Tomorrow. Please use the video posted yesterday to help with error analysis and/or calculations.

2.  Please complete the take-home quiz – due in class tomorrow. Hint:To complete this analysis you need to think how you completed Lab 8 – Precipitation analysis. I have reposted 2 video that will help with your understanding of basic premise of precipitation analysis.

Stoichiometry 4a – Precipitation – limiting reagent – quiz.pdf
View Download 

2 :Lab 8 introduction – A review of the basic premise of this precipitation analysis lab. I have it starting at the midway point where I begin my discussion of the lab.

 

2 :Lab 8 review –  this will help with how to calculate with a precipitation lab setup.

 

________________________________________________________________                                     Jump to:  Friday Homework

10/28 – Friday – A Day – 2, 3a Lab/4 

Main focus – 
     
    a) To perform the analysis of carbonates (Lab 9 ).
                                                          

    b)  To take a surprise quiz

Period 2,3a  – Collect Golden Arches Quiz

1.  Identification of Sample A or B – Visual identification of the salts, Q and A of the Lab. 

2.  Bernoulli’s principle demos – Discussion of Bernoulli’s principle in explaining how the aspirator                                                                    works.     

3.  Complete the data collections of Lab 9 – The NaCl (aq) solution (product) is being heated to evaporate off the water.

4.  Review of Take- Home quiz.

5. Take an in-class quiz on precipitation (surprise?) 🙂         

Period 3b  – Collect Golden Arched Quiz

1.  Complete the data collections of Lab 9 – The NaCl (aq) solution (product) is being heated to evaporate off the water. – we did not get to this today.. we will complete this Monday..

2.  Review of Take- Home quiz.

3. Take an in-class quiz on precipitation (surprise?) 🙂                                                                                                                 

 

.______________________

Lab 9 – Analysis of Sodium Carbonate and Sodium Hydrogen Carbonate 

Lab 9 – Determine the identity of the carbonate by reacting the 2 salts with HCl to produce NaCl.  How much NaCl is made will determine the identity of the salt.   
 
           The salts are either:          Na2CO3     –   sodium carbonate –  washing soda   
                                                              NaHCO3    –   sodium hydrogen carbonate –  baking soda                                                                                                                                                                                                                      This a NOT a precipitation analysis lab but it an Analytical Lab as we will use stoichiometry to identify the starting salts by using how much NaCl is produced by reacting them with HCl.                                                                                                                                                
LAB 9 – Unknown carbonates Lab.pdf
View Download
 
Data gathering for Lab:
      a) mass out unknown carbonates A or B in an evaporating dish
     b) add excess HCl till the reaction reaches completion.
     c) place the evaporating dish on a hot plate under the fume hood (evaporating off the water to                        recover NaCl)
 
Today:
 
     d) MASS OUT the evaporating dish and the dried NaCl (aq) 
     e) Determine the experimental mass of NaCl.
     f) Determine the Theoretical mass of NaCl produced from each of the possible 2 chemical reactions.
     g) Identify the unknown salt based on your calculations.  
 
 

Lab 9 review:

 

__________________________________________________

10/28 – Friday’s Homework: –

1.  For All Classes – Please complete the Data, Calculations, Results and the conclusion of Lab 8 – due Monday. Please use the Lab 7 review video posted below to help with error analysis and/or calculations. 

I also have reposted the Formal Lab REQUIREMENTS BELOW to check you have completed all required sections correctly. 

2.  Please complete the NEW take-home quiz – due in class Monday. Hint: no hints needed!!

Stoichiometry 4c – Precipitation – limiting reagent 21-22 quiz .pdf
View Download

Maybe reviewing the key to last nights take-home quiz could help. Also Monday nights homework had videos that reviewed these concepts.

Last Nights Golden Arches Quiz Key:                                                                                                                         Stoichiometry 4a – Precipitation – limiting reagent key p .pdf                                                                         View Download                                                                        

3.  Please view the lecture below and complete the questions 1 and 2 (on the back) the limiting reagent intro demo new worksheet that was given out last week. It was last weekends homework. 

Question 1, 2 of the backside (You did questions 3 and 4 Monday!)  uses the concept of equilibrium with our  ICE tables.

 
Limiting reagent intro demo new worksheet.pdf
 

 

1 : Lab 7 review –  This might help with your calculations!

 

3 : Side 2 of Friday’s homework –  Teaches the chart method!

 

______________________

 Lab 7 – Synthesis of Copper Iodide (and determination of the empirical Formula of copper iodide)

Lab 7 – Synthesis of Copper Iodide.pdf
View Download

This Lab will be our first formal lab.  I am giving out a data worksheet to keep you organized in your data collection but it will not be handed in.  You will write a data section and calculation section in your formal lab write-up that will be in a google doc that will be shared to you in next couple of days.

 Cu (s)  +  I2 (g)  —>  Cu? I?  

 Objectives:  1. To determine the empirical formula of the salt (product).

                        2. To determine the percent yield of the salt.

 The lab will be written up in a shared google doc according the following rubric:

 
LAB 7 WRITE- UP REQUIREMENTS:
 
 Formal Lab write-ups Examples:
 
AP Chemistry Example
 
 HERE IS ANOTHER EXAMPLE (link to a past AP student’s lab last year)
  
 I am requiring these sections below to be titled and included in your lab report but you are making this lab your own.  Although we did the same data collection and experiment, you are to make your lab unique in the lab write-up.  You will spin this lab to your interests by writing a unique background that will cover a least a page single spaced or 2 pages double spaced.  Use this opportunity to research something that may relate to your experiment.  This is something that you will bring back into your discussion in your conclusion.  This could really be anything related to your experiment or the Fast Plants BUT you must direct your discussion to your Question and then Hypothesis. 
 
1: Title Page – Your name, Date, Title of experiment
 
2:  Background – Your background is like a literary review of the topic in a published study. I am not asking you to write a term paper on the Fast Plant but I am asking you to write an essay on the ANYTHING that is remotely related to this investigation.  Develop your Background so that your discussion eventually LEADS to a Question that you will test with your Hypothesis.  Write it as a prosecutor would deliver their opening statement to set the stage for their argument. I know this is open ended but this is how you make this lab your own.  Do make this a cohesive piece of writing and you may probably need to investigate this information.  At the end of the lab I will ask for your resources, so make note of where you are gathering information. DO NOT MAKE THIS a bunch of unrelated ideas or facts.  I gave you some example below from past students of mine so take a look to get a feel of what I am asking. This part of your lab should be 1 page single spaced or 2 pages double spaced.
 
3:  Objectives/Hypothesis: We normally use objectives here instead of Hypothesis as we are trying to find something.
 
4.  Materials: List all chemicals, equipment and tools used.
 
5: Procedure:  Step by step instructions on how you would complete this experiment. Please bullet this section!
                                  A good procedure is one that another could easily follow to repeat the experiment successfully.
 
6:  Data:   Graphs, Data Tables, etc.
                    Please make a Data table, like the one’s you have had from my handout of other labs that include 
                    those values that you actually measure AND those that you calculate for.
 
                    * You need to pay close attention to units, significant figures , and precision of equipment.
 
                    * You should provide the actual ratios (non-rounded) to use in your error analysis.
 
7: Calculations and Chemical Formulas:   On a separate page, provide all calculations and chemical  
                                                                              formulas that are pertinent to the lab.  You could do this neatly on 
                                                                              piece of paper and then scan or take a picture with your phone and                                                                                                            insert into the shared doc.  No separate piece of paper that is NOT                                                                                                              inserted will be accepted.
            
           *Example: Your percent yield calculation requires a balanced chemical formula that will be determined                                                                         from your empirical formula of copper Iodide.
 
8: Results:  Summarize your data, but do not make conclusion statements. This will be a short section.  A    
                        couple sentences will usually suffice.  This summary will only report the most important information  
                        that coincides with the objectives written.  
 
                        In your lab conclusions, your first paragraph was really a results section.
 
9: Conclusion:  This section will be heavily scrutinized.  Here is where you get dirty with the data. What is the data inferring about copper iodide?  What are the implications or possibilities because of your outcomes.  What could be further investigated?  
If you get vague you will lose points. You must fully develop your points and support them with logic! Remember that many experiments are built from the conclusions of other labs.  This means your points in your discussion will not be facts but just very good possible explanations.  Another experiment would be needed to test the validity of these statements. However,  if you support your statements with solid logic from evidence collected in the lab then you are addressing all the possible implications from YOUR WORK or experiment.  In this point of your conclusion you will be MAKING A LEAP from your work based on data analysis to a POSSIBLE implication Chemically for copper iodide.  If you do this by tying the Background discussion with your discussion here it will result in very will impressive lab write – up! 
 
Please make sure your conclusion covers three basics:
 
            A:  DATA analysis:  complete detailed analysis of the the hard data collected.
                      This has nothing to do with error analysis!!! What does the data suggest?  The data “suggests” or there is a                           possibility. Use the Results section and objectives as a guide  here.  What was your formula?  Is it                                           empirical? Molecular?  What is ratio represent  chemically?  How strong is the evidence that your formula                           is what you think it is?  How does the percent yield support or not support your ratio here?
 
            B:   A LEAP:  You need to explain what the data means in terms of the chemistry of the compound. This                                                                  really the reason for the investigation.  Fully develop your thoughts based on your evidence.  
                                 Be logical and make your case as if you were a lawyer trying to convince a jury of your argument.
 
             C:  Error Analysis:  What are the possible limitations in your lab.  Every experiment has limitations. What    
                       were the limitations in this experiment. What could be done to narrow our approach to better the 
                        questions you laid out in this lab.  
 
                                                    *Your guide here is your actual ratio and your percent yield!
 
* DO NOT MAKE comments that are not logical and are not supported by the evidence.  This is an area of conjecture and speculation so it cannot be wrong unless you do not fully develop your thoughts and support your statements with sound logic.  
 10. Sources – Just give me web address of the sites that you got information from. 
 
End of week 9!