NEWS PAGE

 

1. CHEM 101-------Please read along in your textbook and practice working problems as the information is completed in lecture. We will be covering solids in Chapter 12 of your text.

Chapter 2 - Example 2.8-2.11, 2.18- 2.25, 2.27, Questions 1, 5, 15, Problems 31, 33, 35, 45, 51, 57, 61, 69, 75

Chapter 3 - Example 3.1, 3.3

Chapter 4 - Example 4.7, 4.12

Chapter 6 - Example 6.1 - 6.4, 6.10, 6.11, 6.12, 6.13

Chapter 5 - Example 5.5 - 5.9, 5.20, 5.23, 5.25

Chapter 7 - Example 7.1, 7.2, 7.4, 7.5

Chapter 8 - Example 8.1 - 8.6, 8.9, 8.10 (Test 1 after completion)

Chapter 11 - Example 11.1 - 11. 9, 11.11, 11.15 - 11.17, Problems 23, 25, 31, 51, 59, 75, 77, 125 (Test 2 after completion)

Chapter 12 - Exercises: Questions 5, 6, 8, 9, 13, 15, 27, 29, 31 -- Problems 35, 45

New practice problems have been added:

Chapter 9 - Example 9.1, 9.2(a,b), 9.13(a,b), Skill Builder 9.1, Questions 3, 13, Problems 31, 54, 49c, 57c

Chapter 10 - Example 10.2, 10.4, 10.5, Skill Builder 10.2, Questions 3, 7, 17, 19, 21, Problems 45, 47(c,d), 49(a,d)

2. CLAB 124------- All Sections:

Please be prepared for experiment 10. Please remember to print and bring to class the modified procedure for the Buffers experiment that is a link on the Information Sheet. You should read the introductory material and the procedure in your lab manual (or modification if applicable). Be sure to prepare an outline (summary) of the procedure in your notebook. Remember to bring your lab manual and notebook to class and wear proper lab attire. Please also bring a calculator (does not need to be scientific). Please study the link on the class web page for Common Laboratory Operations and Apparatus.

Your lab reports for experiment 9 will be due.

Clab 124 Experiment 3 report

Raw data: Table for part A to include fp of water, fp of each solution mass of each solute, mass of water for each solution.
Table for part B with fp of each soultion, mass of water, mass of HOAC each solution.

Sample Calc: A-Calculate molality of each solution, calculate fp depression each solution
B- Calculate for run 1, total molality and apparent molar mass
Table I from lab manual with your numbers to proper number of significant figures
Excel graph with table of values
% error calculation

Results: A- molalities and fp depression for sucorse and potassium nitrate
B- Extrapolated value of molar mass from intercept, % error (one value)

Discussion: A- compare fp depression for the two solutes- one should be twice the other
B- discuss % error and R squared value

Lab report experiment 4 instructions.

Raw data: Part I -Molarity of oxalic acid, volume of concentrated NaOH used in dilution
Table of initial and final buret readings for oxalic acid and NaOH Runs I, II, III and IV (if you had one)
Part II - Mass of vinegar used, volume indicated on graph for equivalence point, volume at which indicator showed the end point. Also include the graph from LoggerPro.
Sample calculations: Part I - Dilution calculation for NaOH
Calculation of normality of the standardized NaOH (run 1)
Calculation of average normality of standardized NaOH (average only runs that agree ±.002N)
Part II - Calculation of percent acetic acid in vinegar using volume indicated on graph when second derivative was closest to zero and calculation of the same using the endpoint (where the indicator changed colors).
Results: Part I -Table of concentrations of NaOH for each titration run. Average value for concentration.
Part II – Value(s) for percent acetic acid in vinegar (both methods).
Discussion: Discuss your answer for percent acetic acid. Is it reasonable (near 5%)? Which standardization runs did you include in your average (why). Discuss any errors that may have changed your answer.

Lab report experiment 5 instructions.
I               Raw data – Table of volumes and temperatures for the 3 runs
II             Sample calcs. – Three graphs from Logger Pro for room temp.  Show line fit and equation of line for one graph only that is nearest to straight line.  Two additional graphs (one for low and one for high temp.) with line fit and equation.  The order should not change with temp. There will be a total of 5 graphs.  Mark the temperature on each graph.
Show calculation of “k” for each temperature (pseudo rate law constant).
III            Give order of reaction.  Make table of “k” values, one for each temperature.

IV            Discuss the effect of temperature relative to the rule of thumb.  Discuss any concerns or errors

Lab report experiment 6 instructions

It will be easiest to do the report in 3 separate sections A, B, C as though there were three reports (but one submittal).

A. Chrom.- Raw data: list the stationary phase and mobile phase for thin layer. Give distance traveled by solvent, blue dye and red dye.
List the stationary and mobile phases for the column. Samp calcs.: calculate Rf for red and blue dyes. Results: Rf values. Discussion: Describe what you saw.

B. Cations- Raw data: Give your observations for each step. Samp calcs.: Give balanced equations for all reactions Results: List cations found. Discussion: describe the 3 test tubes that I checked.

C. Ion Exchange- Raw data: Give volumes, mass, concentrations. Samp calcs.: Show equation I placed on board. Results: % efficiency Discussion: Discuss result.

Lab report experiment 7 instructions

Raw Data- Concentrations of stock solutions, recorded pH values and your assigned pH.

Sample Calcs. - All the calculation I put on the board to get volumes for your assigned pH value.

Results - The volumes that you calculated for HOAC and NaOAC.

Discussion - Discuss (expalin) each pH value you recorded in terms of what one should expect for such a solution.

Lab report experiment 8 instructions

Raw Data: Mass of acid, unknown letter, concentration of NaOH, Volume at which indicator turned color

Sample calcs: Two graphs with volumes shown for 2 equivalence points, all of the calcs. I put on the board for both eq. pts.,

Results: Two values for molar mass, identity of acid (from listing in lab manual)

Discussion: Discuss your certainty in the identification of the acid. List any errors.

Experiment 9 instructions:

Use the sample lab report linked on the Information Sheet as a template.

http://www2.southeastern.edu/Academics/Faculty/delbers/Samp_equ_exp.pdf

Use your numbers and use the sample report as a template. Your report will not be graded if this format is not followed.

Experiment 10 instructions:

Raw data: A-voltages of single cell, parallel and series connected cells.
C- Masses of + copper electrode before and after and - copper electrode before and after. Table of current vs. time.

Sample Calculations: A- Theoretical value of voltage - single cell, series connected.
C- Calculate Faraday's constant as I did in class for + and - electrodes. Calculate % error for each electrode.

Results: A: Give measured and theoretical voltages for single cell, parallel and series connection.
B: Give 6 reactions. Put a check above the arrow for reaction that occurs and an X above the arrow for the reaction that does not occur. Finally, give the activity series (X>Y>Z) where X, Y, Z, are the symbols for the chemical elements studied.
Give the values you calculated for Faraday's constant and the % errors for both electrodes.

Discussion: Discuss your results.

 

End of Semester Reminders

Make-up exams (comprehensive) will be given the last week of classes May 2, 3, and 5 at 11:00 am, 2:00 pm and 12:30 respectively. You must give me written notification no later than 4:45 pm, Wednesday April 27 indicating your selection of time. Please remember that you must have an excused absence in order to be eligible for the make-up exam.

Optional extra credit assignments for lecture classes are due the last class meeting (not the day of final exam). The due date for lab classes is the day of the final exam. “UCM” passes are due at times for extra credit assignments. Print your name on the back of each pass.

Final exams are as listed on the official schedule with the exception for graduating seniors. These tests will be given early (the week of finals).

Lab finals are as indicated on the lab schedule.

Please bring a type “F” scan form calculator and pencils.