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## Q1 : Week 9  – 10/30 – 11/3

<- Week 8

#### Refresh this page every time you arrive!  I update this daily!!!

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

LAB 5 – Percent by Mass of water in a hydrate is Late!

Lab 6 – Empirical Formula of a Hydrate is Late!

________________________________________________________                                        Jump toMonday Homework         10/30 – Monday A Day 2/3a Lab, 4

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

Period 2/4 :

1. Flaming Tube Demo –

a) Which reactant was Limiting the reaction?

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

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 last Thursday.

Limiting reagent intro demo new worksheet.pdf

2)  Reviewed 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

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

3)  Modeled the 1st side of Stoichiometry 3 with Ice Table.

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 1) – Molarity limiting reagent  p.pdf

Period 3a :

1. Note-taking of how to complete the Lab 8 – Precipitation Analysis of an Alkali Carbonate

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 Collect the precipitate and place in oven.

Run Lab 7  – isolate the precipitate and place in oven

________________________________________________________________________                                                                                                  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

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)
e) filter precipitate with aspirator and Buchner funnel.
f) dry out precipitate (put measured filter paper on watch glass) in oven.

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 types 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 toTuesday Homework / top 10/31 – Tuesday – B Day – 2, 3b/4 Lab

Happy Halloween!         Main focus –

a) To Review the ICE table method of determining the limiting reagent for solutions and the precipitation reaction.

b) To perform or take notes on a precipitation analysis lab and determine the limiting reagent and excess chemical.

c) To Perform pumpkin stoichiometry!

Period 2/3b :

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

2Pumpkin Stoichiometry – demo tomorrow.. (ACT test going on in school).

Period 4:

1.  Lab 8 continues

2. mass of precipitate —-> identification of Alkali carbonate

Pumpkin Stoichiometry Presentation:

______________________

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

Data gathering for Lab:
a) dry out carbonates with microwave.
b) attain dried mass of unknown carbonate.
c) Dissolve in water (about 200ml)
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.

1.   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
Stoichiometry 4 – Precipitation – limiting reagent Key p.pdf

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

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

____________________________________________________________________________             Jump toWednesday Homework / top 11/1 – 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.
b) To complete all calculations of Lab 8 and the error analysis.
c) To identify the Limiting Reagent/excess/amount of precipitate (product) through stoichiometry.

Period 2, 3a –

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

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

3.  Complete the Stoichiometry box for Lab 8/ review of homework

Period 4 –

1Complete the data collections of Lab 8/ identify the salt – for those that did not have data

2. Complete the Stoichiometry box for Lab 8/ review of homework

______________________

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

Data gathering for Lab:
a) dry out carbonates with microwave.
b) attain dried mass of unknown carbonate.
c) Dissolve in water (about 200ml)
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

1.  Please view the Lab 8 – review video below if you do not completely understand the lab 8.

Lab 8 is due tomorrow!!!We finished it in class but make sure the lab is handed in tomorrow!

2. Complete the form based on Lab 8’s calculations.  Today in class we completed the data and calculations for this lab. We determined the mass of the experimental precipitate AND the theoretical through the stoichiometry. This lab was a hands-on approach to precipitation analysis and precipitation reaction in general.  Monday’s/Tuesday’s homework were baseed on the same concepts!  IN the FORM BELOW WE ARE PRETENDING that we are doing the same lab and will follow the same steps as we did today/yesterday (with given values of mass of your unknown salt and filter paper).  IF you need to please review these calculations with the video below.

1. Lab 8 review –  This might help with your calculations and tonights form!

2. Gravimetric Analysis Lab  –

_______________________________________________________                               Jump to:  Thursday Homework /top  11/2 – Thursday – B Day – 2, 3b/4 Lab

Main focus –

a) To review Precipitation analysis through Lab 8 and Gravimetric Form

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

Period 2,3b,4 –

1.  Gravimetric Form Review/lab 8

2.  Lab 9 – Analysis of Carbonates

a) introduction                                                                                                                                                       b) collect initial data                                                                                                                                             c) predict outcomes

3.  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

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)

1.  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

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

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

________________________________________________________________                         Jump toFriday Homework/top  11/3 – Friday – A Day 2/3a Lab, 4

Main focus –

a) To complete the analysis of carbonates (Lab 9 ).
b)  To take a surprise quiz! SHHHHHH!

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

3.  Review of Take- Home quiz.

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

5. Pumpkin Stoichiometry?

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?) 🙂

4. Pumpkin Stoichiometry?

.______________________

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

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:

Today’s Pumpkin Stoichiometry :

1.  For All Classes – Please complete the Results and the conclusion of Lab 7 – Friday 11/10. Please use the link posted belwo posted below to help with error analysis and/or calculations.

All instructions along with examples can be found in the link below.

Formal Lab Write-up Instructions: https://mrgrodskichemistry.com/lab-7-formal-write-up/

Please hand in all Labs (4, 5, 6, 8, 9). They are all due Monday, 11/6. Lab 6 and 8, 9 do not have conclusions.  Labs 1 – 6 are Late!

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

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

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

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 Monday’s 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

4Study for test 2 – Link to Test 2 Notes

Monday you will have the part of the test that will be very much like the last 2 quizzes and multiple choice questions that are from all our skills learned from Analytical Chemistry.

Here are the keys from the last 2 quizzes :

Stoichiometry 4c – Precipitation – limiting reagent key p .pdf