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  Q1 : Week 6  – 10/5 – 10/9

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

Please Make sure Your read all instructions for all assignments.    

LAB 4 – Electrolysis of copper (II) Chloride is  Late!

LAB 5 – Electroplating of a Brass key is Late!

LAB 6 – Thickness of Foils is DUE Wednesday 10/7! 

  ___________________________________________                                                                                                             Jump to: Monday Homework     10/5 – Monday – A Day – 1AB

Main focus –

a) To introduce alloys (substitutional & interstitial) and introduce  galvanic corrosion
b)  Review Unit Cell Calculations Problems.

 

Period 1:     

1. To review the Unit Cell Practice Problems
 
Unit Cell Practice Problems II.pdf

Unit Cell Practice Problems II Key.pdf                                                                                                                     View Download

 
2. Alloy discussion – Substitutional vs. Interstitial  alloys / Galvanic Corrosion

Alloy lesson – How adding different metals into a metal crystal will change the metals properties 

       Examples:  Steel, Stainless Steel (Cr prevents the oxidation of Fe )

       Keep Galvanic Corrosion for the second day.. (get to the Alloys!)

 
Steel, Brass, Bronze, 
Statue of Liberty
sacrificial anode
electrodes on boats 
 
Classwork:
Alloy worksheet.pdf
View Download

Alloy worksheet key.pdf                                                                                                                                           View Download

 

3. Test 1 – review worksheet – Hint!

 

 

Alloy Presentation for class lesson:  

Alloy introduction video : Stop at  23:00 (alloy lecture part)

 

 

_____________________________________________________                                                                                                            jump to:  top         10/5 – Monday’s Homework: – 

Study for TEST 1 – Tuesday –  10/6
IF you do not know how to do something today you should to review the skill from the previous resources posted.                            
 
Test 1 topics:  – 
Please go back the appropriate worksheets, keys,and lectures in the past 3 weeks to review the following concepts
1.  Coloumbs Law:  
 
No calculations with the formula but you should be aware how it applies to atoms ability to oxidize or reduce, solubility (why some ionic solids will dissolve in water while others do not or precipitate).
 
2.  Voltaic Cell/galvanic cell 
 
 Diagram, determining anode, cathode, charges, flow of electrons, salt bridge flow of ions, E0 calculation, use of reduction potential table,  writing balanced half reactions and overall reactions, predicting the voltage change when concentrations change (Le Chateliers Principle), molarity (M), predicting precipitates that would lower the molarity of certain ions when they become solids, voltage vs current.  Spontaneity and equilibrium, The U diagram.
 
3: Electrolytic Cell – 
 
Diagram and label all parts with flow of charge from a power source.  Predict the products at each anode.   Calculating the moles, molarity, or grams of the products using total time, amperage and Faradays constant.
Determining E0 cell, half reactions, overall reaction, spontaneity.
 
 Example 17.9 in Textbook gives 2 more problems with solutions
 

Electrolysis quiz Review Video is posted below:

4:  Unit Cell and alloys

Textbook: 10.6  – Lattice Structures

Basics of interstitial and substitutional alloys,  calculations using density, lattice constant and atomic radii with FCC or BCC.  Conversions, and use of Avogadros number.

 
There is no need to memorize the conversion factors (pm, nm) but you need to know what the FCC or BCC looks like and you should be able to figure out how many atom exist in each FCC or BCC. You should be able to complete all conversions of all the worksheet and Lab (4). 
 
 Example 10.15 in Textbook gives 4 more problems with solutions
 
 
Calculations of Close Cubic Packing Structures.pdf
View Download
 
Calculation with Close Packing structures Key p.pdf
View Download
 
Crystalline Unit Cell Problems.pdf
View Download
 

Crystalline unit cell problems key p.pdf
View Download

 
Unit Cell Practice Problems.pdf
View Download   
                                                                                                                                                                                        Unit Cell Practice Problems Key.pdf
 
Unit Cell Practice Problems II.pdf

Unit Cell Practice Problems II Key.pdf                                                                                                                     View Download

  

Here is a Link to Purdue University’s resources on Unit cell calculations: 
 
5.  Review your 2 graded quizzes.  I have posted some blank quizzes.  *If you cannot print from your school computer, use your phone or another computer.
 
 Blank Quiz Quiz Key
Voltaic Cell quiz 1.pdf
View Download 		Voltaic Cell quiz 1 key.pdf                                          View Download
Voltaic Cell Quiz 2 – 22-23.pdf
View Download 
Voltaic Cell Quiz 2 – 22-23 KEY.pdf
Electrolytic cell quiz .pdf
View Download      
Electrolytic cell quiz key p.pdf

  View Download                                                                                                                       

6. Review todays “Review worksheet” with key below or with the video below:

         
Blank Test 1:   LINK                                                                                                                                                                                        
Key to the Test 1:   LINK

                                                                                           

Voltaic Cell Quiz Review Video:  

 

Electrolytic Cell Quiz Review:  

 

Today’s Review of Test 1 – “REVIEW WORKSHEET”: 

                     AP Chemistry – Electrochemistry and Unit Cell Test Review –                                      

 __________________________________________                                                                                         Jump to:  Tuesday Homework / top
10/6 – Tuesday – B Day – 1,2B

Main focus –

   

a) To Take Test 1 – Voltaic/Electrolytic Cells/Cubic cell calculations/alloys                                                                                                                                                                                                                              
        Period 1,2:
 
         
 
1. Complete Test 1 –   one period test!   
 
2.  Complete Lab 6 – 

______________________________
Lab 6 – Thickness of Metal Foil Lab

 

LAB  6  – The Metal Foil lab – Determine the number of atoms high a copper foil and aluminum foil are using volume, density and unit cell calculations.

Objectives:

1. Calculate the Thickness of an aluminum and copper foil (thin piece of metal).

2.  Determine the number of atoms high a copper foil and aluminum foil are using volume, density and unit cell calculations.

The metal foil lab activity is not a formal writeup but please complete it as per the procedure in the handout that I gave.  A piece of paper with your work neatly written with units and sig figs showing all calculations will suffice.

Discussed the volume unit relatives cm3 = ml and the conversions of m3 to cm3metric prefixes:   

K H D [   ] d c m  —–>  micro, nano, pico

Conversion large number = small unit —–> small number = large unit
 
Lab 6- thickness of foils – 2025.pdf
View Download
  

Thin Foil Lab Instructions:

 

 

Thin Foil Lab measurement : If you still to measure the mass or dimensions of Al or Cu please use this video to grab those measurements

 

 __________________________________________________                                                                                     Jump to:   top                                10/6 – Tuesday Homework: –

 The Homework is very light!   ↓

                          HAVE AN UNBELIEVABLE EVENING!

 

_______________________________________________                                                             Jump to:  Wednesday Homework / top 
10/7 – Wednesday – A Day – 1AB

Main focus –

 a) To hand back and review Test 1
 
 b) To begin the Mole concept/particle theory
                                                                                                                                                                                     
                                 
 Period 1:   
 

1. Hand Back Test 1a

Electrochemistry Test Key  

 

2. Mole concept and particle theory begins in class 1 –  We have used mole concept and particle theory in our Amperage/Faraday calculations and in out unit cell calculations BUT we need to formally review and solidify these concepts to begin the Analytical/Stiochiometry part of the course. 

————-1800————————1803————————–1831———————-–1860———–

                   Voltaic Pile                           Humphrey Davis                      Michael Faraday’s                  Mole Concept                                        created!                       electrolysis of water                  Laws of electrolysis                   created

                                                                                                                                                                                    ↑

                                                                                                                                       The Science of Chemistry Began!                     

1) G(r)eeks to John Dalton

2) Seeing atoms – Scanning Tunneling Electron Microscopy – (pizo electric crystal)

The need for a particle theory and mole theory.  They are deeply intertwined.
   

Richard Feynman said in Volume One of his Lectures on Physics:

If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generation of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis that all things are made of atoms — little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another.

 

                                                                                                                

_______________________________________________________                                                                   Jump to:   top                       10/7 – Wednesday Homework: –

 

 *Test Corrections – Please complete the blank test and hand in Tomorrow.

 Mole Concept/particle theory Officially begins:                                                                                                                                                          

1.  Please view the last 17 minutes of the Greeks to Proust – percent error lecture below.  What I am doing here is transitioning from Joseph Proust (Law of Definite Proportions developed from percent by mass expirements) to discuss Hydrates.  These are salts (Ionic compounds) that have water inside the crystal of ions in an exact ratio.  We will work with with Hydrates in our next 2 labs.

 
2. Please complete the empirical&molec ditto hydrate combination.pdf worksheet and Review with key. 
       This worksheet uses percent by mass to build the formula of compounds. Percent by mass was first used by Joseph Proust when he found that each chemical compounds has a unique percent by mass of the element that make it.  What he really discovered was that each compound has a unique ratio of elements (chemical formula!) but there was not particle or mole concept developed yet to make the formulas from the percents.
   * If you need, I have posted a video below that review these problems if you need more help.
                                                                                                                                                                                                                             
empiri&molec ditto hydrate combination.pdf
View Download                                                   
                                                                                       
empiri&molec ditto hydrate combination KEY p.pdf
View Download

                     

1 : Greeks to Proust – Percent Error Lecture : It will start at the halfway point! 

2: Video Review of the Empir&Molec worksheet  : Calculating chemical formulas (empirical and molecular formulas) from percent mass data with Hydrates!

 

  ____________________________________________                                                                             Jump to:  Thursday Homework /top
10/8 – Thursday – B Day – 1,2B  

Main focus –
       
a)  To contine our journey through history that develops the particle and mole theories that allowed the science of Chemistry to begin.

                                                                                                                                                              

b)  Joseph Proust – Guy Lussac – Avogadro – Cannizzaro  

c)  To compare and constrast the hydrates and anhydrates.

d)  Analytical Chemistry begins with determining percent by mass (Hydrate lab) –

Our  homework has been based on starting with % by masses to determine the chemical formula (fixed ratio of how many atoms) or we had to get the % by mass through combustion analysis.  We will perform the type of experiment that was done after the Solvay conference which was first step to determining the chemical formulas.

Period 1-2:

1.  discussion of homework – the building of chemical formulas

– empirical formulas

– molecular formulsa

 

2.   Joseph Proust –> John Dalston –> Guy Lussac —> Amedeo Avogadro!!!!!

Karlsruhe Congress – September 3, 1860, Germany.

Mole concept and particle theory begins in class 1 –   

—————1800————————1803————————–1831———————-–1860———–

                   Voltaic Pile                           Humphrey Davis                      Michael Faraday’s                  Mole Concept                                                           created!                       electrolysis of water                  Laws of electrolysis                   created

                                                                                                                                                                           ↑

                                                                                                                                 The Science of Chemistry Began!                        

 

Cannizzaro’s efforts exerted a heavy and, in some cases, an almost immediate influence on the delegates. Lothar Meyer later wrote that on reading Cannizzaro’s paper,

I was astonished at its clarity, the little manuscript covered all the important points in dispute. It was as if scales fell from my eyes, doubts vanished, and a feeling of calm certainty came over me.

 
 

Richard Feynman said in Volume One of his Lectures on Physics:

If, in some cataclysm, all of scientific knowledge were to be destroyed, and only one sentence passed on to the next generation of creatures, what statement would contain the most information in the fewest words? I believe it is the atomic hypothesis that all things are made of atoms — little particles that move around in perpetual motion, attracting each other when they are a little distance apart, but repelling upon being squeezed into one another.

3.   Law of Combining Volumes,

Law of Combining Volumes Diagrams.pdf
View Download
 
Law of Combining Volumes Diagrams key new.pdf
View Download

 

 

                                                                                                                    

Particle / Mole Theory Presentation (): 

_______________________________________________________________________                                                                                                                                  Lab 7 – Percent mass of water in a Hydrate

Objectives:

1. To determine the percent by mass of water in copper (II) sulfate pentahydrate, CuSO4 • 5H20

2. To calculate the theoretical percent by mass of water  of copper (II) sulfate pentahydrate.

3. To determine the accuracy of your results.

 

LAB 7 – copper sulfate pentahydrate lab.pdf
View Download

Let’s look at an ionic crystal that has no water called anhydrate.  
 
Lets look at copper (II) sulphate : CuSO4  :

 This image was build by X-ray imaging of salt.

Now it is more complex than the crystal above for NaCl because we have a polyatomic ion in the crystal.

The Yellow is the Sulfur attached to 4 oxygens (red).  The brown color (i think its brown) is the copper.

Notice regular repeating pattern.
The sticks represent the bonds or the attractions between the ions.

Its hard but if look inside the crystal there is one Cu per sulfate ion.

 
Lets look at the formula of the hydrate of the same salt : copper (II) sulphate pentahydrate: 
 
 CuSO4 ● 5H2O

Notice the Dot between anhydrate and water.  This Dot means “WITH” and not to multiply.   

There are exactly 5 water molecules for every 1 Cu+2 and  1 SO4-2 in the crystal.

 
Lets look at the crystal formation of copper (II) sulphate pentahydrate: 

 You will notice that water (it has 2 white hydrogen atoms) molecules are situated inside the crystals at particular regions in the crystal in exact ratios.  This is a fixed ratio (stoichiometric ratio).

It is hard but you can see the 5 water molecules per 1 copper ion and 1 sulfate ion.

What makes it hard is that the crystal repeats in all directions.

The water can be removed from the salt by heating it.

                                                 CuSO4 • 5H20   ——->    CuSO4  (s)     +      5H20  (g)                                                                                                                               Heat                                         
                                                                                                                                                                                                                 Today we will be able to do the following:           
         a) Determine. the mass of your annhydrate (dried hydrate)
       b) Determine the mass of the water (THAT was in your crystal)
       c)  calculate the experimental percent by mass of water:
 
            % by mass =  Mass of the part (mass of water missing)         x     100  
                                    Mass of the whole (mass of original hydrate)
 
         d)  calculate the Theoretical percent by mass of water using the chemical formula of the hydrate:
                 
                                                                                    CuSO4 • 5H20
 
                    Given the formula above, determine the percent by mass of water of the hydrate:
 
                                           Assume you have 1 mole of CuSO4 • 5H20:
 
                                Thus in 1 mole of the hydrate you have 5 moles of water:
 
                                For every one (CuSO4 • 5H20) you have 5 moles of water.
 
                                                                         1               :               5
                                               
                                    Ratios of how many!!! This is why we need a mole theory!                    
 
                               
                          % by mass =  Mass of the part (mass of 5 moles of water)         x     100  
                                                   Mass of the whole (mass of 1 mole of hydrate)
 
*Mass of 1 mole of any compound (with a unique chemical formula) is the sum of the atomic masses of all atoms in the formula or molecule. You need the periodic table!
 

Percent by Mass of Water in a Hydrate Lab: 

____________________________________________________                                                                              Jump to:   top                  10/8 – Thursday Homework: –

 

500 – 300BC —————1800————————1803—————————––1831————————-—--1860———–——–1905

     G(r)eeks                    Voltaic Pile                  Humphrey Davis                    Michael Faraday’s                        Mole Concept                Atoms                                                created!                   electrolysis of water                 Laws of electrolysis                             created.                     finally                                                 ————————————————————————————-                                                               accepted!

                                                     ↓

                                                                   Redox

 

*Please read the following below before you begin your homework.

*We will complete next group of historical labs based on what was done as soon as the SOLVAY conference ended.  Chemical formulas will be built based on the percentages of mass determined experimentally.

In Lab 7 we will determine the percent by mass of compound (hydrate) experimentally. SINCE compounds have fixed ratios or chemical formulas, this is a value that can help a chemist analyze and identify it.

In Lab 8 we will build a chemical formula of the hydrate by using the percentages of each part of the compound that we separate.Using the mole concept we will create a how many ratio (chemical formula)!!!

The homework tonight will based on starting with % by masses to determine the chemical formula (fixed ratio of how many atoms).  We will perform these type of experiments that was done after the Solvay conference, which was first step to determining the chemical formulas.

This is the beginning of Analytical Chemistry.

Law of Definite Proportions = the same compound will always have the same percentage of different elements in it. This really meant that the same compounds have the same chemical formulas!! 

 
And the different compounds have different chemical formulas MEANING different ratios of atoms CREATE the different compounds!!!

 

So the Law of Definite Proportions was a HUGE leap forward in Particle Theory! Thank you Joseph Proust!
 
1. Watch lecture 0 below. In the lecture I am modeling how to complete question 1 on the first side of the  Analytical Chemistry I – determining chemical formulas.pdf worksheet and then you will complete question 2 on the first side on your own. (We are using percent by mass to BUILD chemical formulas!!!).                                                                                                                                        When we use the mole concept!
 
Analytical Chemistry I – determining chemical formulas.pdf
View Download
 
2.  Please answer question 2 on the first side of the worksheet and review with key that is posted below.
 
Analytical Chemistry I KEY- determining chemical formulas.pdf
View Download  

 

3. We completed this in class-  THis is not required.

Please view this mole concept lecture BUT start at 27:29 by clicking the video below. It will automatically start at 27:29. It will review the Law of Combining Volumes (by Gay- Lussac).   Please view this until to 34:20.

Please use the Law of Combining volumes tutorial below to complete the worksheet below.  You could just complete the worksheet and view with key, if you get the concept.

 
Law of Combining Volumes Diagrams.pdf
View Download
 
Law of Combining Volumes Diagrams key new.pdf
View Download                                                   

 

1: AP Lecture 0 : Calculating chemical formulas from percent by masses (that are obtained through labs). 

3) Mole and Particle Concept Lecture : It will start at 27:29 when you start this. 

3) Law of Combining Volumed Tutorial : 

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Main focus –             
 
1. To determine the percent by mass of water of a hydrate.                                                                2. To determine the empirical formula of an unknown hydrate.                                                            
Period 1:
 

1.  Complete Lab 7 – percent by mass of water in copper (II) sulfate pentahydrate

– While heating for lab 8, lab 7 was completed.

2.  Complete Lab 8 – Empirical Formula of a unknown hydrate

 

 

___________________________________________________________________________________ 
Lab 8 – Determination of the Empirical formula of a Hydrate

                    *Determine the chemical formula of a hydrate:  

Objectives:

1. To determine the empirical formula of hydrate in magnesium sulfate ____hydrate, MgSO4 • __H20

2. To calculate the theoretical percent by mass of water of the hydrate.

3. To determine the accuracy of your results.

 

LAB 8 – Empirical Formula analysis of Hydrate.pdf

 
We will determine the formula of the hydrate in this lab much like your homework this weekend. Imagine that the work in the class parallels what we do in Lab!  To complete the chemical formula we need to obtain the grams of water lost and the grams of anhydrate remaining from drying out another hydrate.
The grams (how heavy) of water and the anhydrate will be determined the same way as Lab 5.  But we will take these grams (how heavy) and convert it to a how many number (mole concept) to get the ratio of water to anhydrate.
 

                                     What is the MOLE RATIO of MgSO4 to water? 

Because of the conservation of mass by Antoine Levassuer, the mass of  water that is released from the crystal (hydrate) is the same mass that was is in the crystal.  THus the moles of water lost is the water that are in the crystal (in the formula ) .  

 
Formulas of compounds are fixed! (Thanks Joe Proust – Law of definite proportions)
 
Once we determine the mass of water lost, we at the same time determine the mass of remaining part of the salt called the annhydrate.  Convert grams of both parts of the hydrate to moles  and then get a ratio of how many (moles) by dividing by the lowest number of moles.  That ratio is what we will use for the fixed formula! 
 

The Empirical Formula of a Hydrate: 

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500 – 300BC —————1800————————1803—————————––1831————————-—--1860———–——–1905

     G(r)eeks                    Voltaic Pile                  Humphrey Davis                    Michael Faraday’s                        Mole Concept                Atoms                                                created!                   electrolysis of water                 Laws of electrolysis                             created.                     finally                                                 ————————————————————————————-                                                               accepted!

                                                     ↓

                                                                   Redox

 

1. Complete Lab 7 & 8 if you did not do so in class. Lab 7 & 8 are due for both classes. Lab 8 just has calculations and no conclusion but Lab 6 does have a conclusion.  Do not just list errors. Completely explain why your experimental outcome was lower or higher than the theoretical.  
 
– I eliminated the conclusion questions (page 3) for Lab 7 But it has a conclusion that wrote in class.
 
– I eliminated conclusion questions 5 & 6 AND the conclusion for the Lab 8.

 

2.  Please watch lecture 0a, which is posted below with Thursday nights worksheet (side 2 – questions 3 of Analytical Chemistry I – determining chemical formulas.pdf. This the other side of the worksheet that we worked on Thursday night.  We will do question 3 together before you do question 4 on your own.  This weekend we will use analytical chemistry (discovering formulas using particle and mole theory in Combustion Analysis.)  Please read these notes before you begin. 

– Combustion (burning):  
A redox reaction (imagine that) that uses O2 as the oxidizing agent on a fuel (normally a hydrocarbon)
 
                                             C?H?   +    O2    →   CO2     +     H2O
 
                                                      Notice that combustion is a redox reaction….
 
Using the law of conservation of mass by Lavoisier and the idea that every unique compound has a unique formula (law of definite proportions by Proust) we can determine the chemical formula of hydrocarbon fuel if we have the mass of the CO2 and  H2O that is produced.
 
The key to solving these problems are percent by mass!
 
Analytical Chemistry I – determining chemical formulas.pdf
View Download  
 
3.  Please answer question 4 of the same worksheet and review with key that is posted below.
 
Analytical Chemistry I KEY- determining chemical formulas.pdf
View Download

4.  Please complete the Mole Concept Lecture Form which based on our class discussions based on the historical developments of the particle and mole concepts.  If you need you can refresh these ideas below with the Mole and Particle Concept Lecture Video below.

       

  

                                                                        

2: AP Lecture 0a : Calculating chemical formulas from Combustion analysis (that are obtained through labs). 

 

4 : Mole and Particle Concept Lecture :

 
4: Mole Concept Lecture Form:                                                                                                                             

 

END OF WEEK  6!