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Saturday 02:00 a.m. - 05:30 p.m. AC 363
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Thursay 01:00 p.m. - 04:00 p.m. LET 409
WM 320 ADJUNCT OFFICE
Please read the LAB REPORT RULES. Points will be taken from labs which do not follow these rules.
LAB #1: FREEZING POINT DEPRESSION AND SOLUBILITY
The purpose of this lab is to determine or observe how concentration or temperature effects the solubility of a salt in water.
Using the data gathered from the six experiments you will extrapolate to determing the solubilities of the salt at 0 C and 100 C. The extrapolated point are to be determined from a linear and nonlinear graphs and curve fits of your data.
The nonlinear fit or best fit curve will be used to complete the gKNO3/100g H2O column.
After completing these data points, then complete the last table by converting to each of the other concentration units.
1. Extrapolation of concentrations at 0 C and 100 C.
A. Plot your data in terms of gKNO3/100g H2O vs Temp in C, and in terms of log 10 (gKNO3/100g H2O) vs Temp in C
B. Use a straight edge or ruler to make a best fit line for your points on the log 10 (gKNO3/100g H2O) graph.
C. Make sure your best fit lines crosses 0 C and 100 C
D. Find the slope - intercept form of a linear equation for the best fit line you made.
Remember: y = mx + b.
m is the slope of the line [rise over run].
b is the y - intercept, the y value at the intersection of your straight line with 0 C.
E. Draw a nonlinear curve that best fits your data points on the gKNO3/100g H2O graph and extend it to cross 0 C and 100 C.
F. Record the intercepts of this curve in the tables for your extrapolated points at 0 C and 100 C. In the column for the log 10 (gKNO3/100g H2O) remeber to enter yyour data so that both sets of values may be compard; 10intercept value = concn in gKNO3/100g H2O EXTRA CREDIT 20 POINTS. Complete the last table of the lab by converting the units of gKNO3/100g H2O into units of mass %, mole fraction [X], molality [m], and Molarity [M]. Then find the osmotic pressure for the solutions in the last column. Make separate plots of wt% and X and plot m and M on the same graph. I will not allow molality and molarity to be the same for this lab since the density of KNO3 is 2.109 g/mL and the FW KNO3 is 101.0 g/mol may be used in the calculations. DOWNLOAD LAB 1 EXTRA CREDIT CHEM111EXTRACREDITLAB1.doc
You will have lab access time to EXCEL during LAB #4.
The graph(s) and tables are due 1 week after LAB #4 in learning center.
LAB #2: ROULT'S LAW
The objective of this lab is to observe how separations are performed. The two methods used to show this are distillation and gas chromatography. What will be observed is a confirmation of the original solution composition and how the composition of the solution changes during the distillation. Two temperature vs volume distillate plots on one graph will be used to show how the pure components and mixture boiling points appear in either the bottoms or the overhead. Gas chromatographs of the original pot mixture and at least 2 cuts, volumes of distillate.
Complete the lab handout with the trial and error @ 90C.
Plot the temperature vs time table created in class for the mixture.
Find the boiling point of the mixture from the temperature vs time graph.
Using the handout with the graphs of the Clausius-Claperon Equation draw a line from the intersection of 760 torr and the mixture line to the temperature axis.
Record the mixture bp temperature on the graph and in your notes.
Compare the boiling points found by the C-C equation and the temperature vs time graph. Use %difference to numerically state whether or not the C-C equation comes close to your experimental bp.Compare the CALCULATED/ESTIMATED boiling point of the mixture with the OBSERVED boiling point of the mixture from the temperature vs time data.
Find the curves for cyclohexane, toluene, and the mixture on the other graph of ln(P/760) vs 1/T in the handout.
Observe the GC analysis of the mixture and label the peaks from the GC chromatogram.
Plot .
80 pts for completing the lab handout. [illustration of apparatus and finding vapor pressure at 90 C]
85 pts for completing the lab handout. [illustration of apparatus and finding vapor pressure at 90 C]
and properly labelling the three lines for cyclohexane, toluene and mixture.
100 pts for completing the lab handout. [illustration of apparatus and finding vapor pressure at 90 C]
and properly labelling the three lines for cyclohexane, toluene and mixture.
and plotting temperature vs time graph
finding boiling point of mixture from temperature vs time graph
and comparing experimental mixture boiling point with the theoretical value found from a plot of the data and using the Clausius Claperon Equation. The comparison should be in units of &delta % and comment written as to whether the Clausius Claperon does or does not agree with your experimental resuls.
110 pts for completing above lab with temp vs time graph plotted from spreadsheet and all done for 100 pts.
LAB #3: REACTION RATE: IODINE CLOCK
From your data you will be finding the reaction rates for several solutions.
The reaction orders are determined by the SLOPES of the 2 ln(concentration) vs ln(time) graphs.
The reaction rates may then are placed in a table so that the ratio method may be used to determine reaction orders for the peroxide and iodide ions.
Record the reaction orders for peroxide and iodide ions and the overall reaction order.
Write the rate equation from the known reaction orders.
Use the reaction orders to determine the rate constant, k, for the reaction.
Write the complete rate equation for the reaction with the numerical value for k.
What are the units of k?
Photocopy your data and calculations pages and hand them into me.
LAB #4 CALCULATIONS AT LEARNING CENTER FOR LABS #1 and #3.
Meet in LEARNING CENTER WM first floor. Go to the back room which is isolated from the open lab area.
THE COMPUTER PORTIONS OF LABS
LAB #4 ASPRIN SYNTHESIS. Lab will be from a handout.
Review STOICHIOMETRY and other relevant material.
Find and make copies of the MSDS sheets requested in the handout.
Be sure to calculate the THEORETICAL YIELD and PERCENT YIELD of the asprin you synthesized.
Keep your sample marked/labelled in a drawer for you to use the following week for analysis.
Keep your lab and data for the analysis experiment. MSDS SHEETS LOOK FOR ISCS CARDS
ONLY DO PART A THE ASPRIN SYNTHESIS
LAB #5 ANALYSIS OF ASPRIN. Lab will be from a handout.
The precise quality of your samples will be determined here.
An ACID-BASE titration will be used to find the mass of asprin in your sample.
Create a graph from the data for each titration.
Record the equivalence point in term of pH and mL NaOH on the graph and in the tables.
Calculate the mass of asprin in your sample
mmol NaOH = mL NaOH * [NaOH]
mmol Asprin = mmol NaOH
mg Asprin = mmol Asprin * MW(Asprin)
Calculate the % mass of aspring in your sample +
ASPRIN PH TITRATION DATA
LAB #4 AND LAB #5 ARE DUE THE WEEK AFTER COMPLETING LAB #5.
LAB #6 pH and Buffers. The objective of this lab is to plot titration data and observe the effects of a strong acid or base on buffer solutions.
Complets ALL of the experiment
DO COMPARE your THEORETICAL results for the different solutions with the experimental readings from the pH meter. SHOW YOUR CALCULATIONS and your reasoning in the comparison.
=========================old lab below=======================
LAB #6 LAB #24 HYDROLYSIS OF SALTS. Lab will be from lab book. Review areas of weak acid and weak base equilibrium. Objective is to find Ka or Kb from pH data.
Here is the starting point for the EASTER fun facts page.
Here is the starting point for the 4TH OF JULY fun facts page
Here is the starting point for the HALLOWEEN fun facts page
LAB #7 LAB # 30 QUALITATIVE ANALYSIS Lab will conducted INDEPENDENTLY..
NO LAB PARTNERS. MAKE NOTES IN SPIRAL/CLOTHBOUND NOTEBOOK TO BE HANDED IN. Photocopy reaction trees and highlight the areas relevant to your unknowns. Create and complete tables of reaction step, reagent, and equation from your notes. Identify the unknowns.
LAB #8 LAB # 30 QUALITATIVE ANALYSIS Lab will conducted INDEPENDENTLY..
NO LAB PARTNERS. MAKE NOTES IN SPIRAL/CLOTHBOUND NOTEBOOK TO BE HANDED IN. Photocopy reaction trees and highlight the areas relevant to your unknowns. Create and complete tables of reaction step, reagent, and equation from your notes. Identify the unknowns.
LAB #9 LAB # 30 QUALITATIVE ANALYSIS Lab will conducted INDEPENDENTLY..
NO LAB PARTNERS. MAKE NOTES IN SPIRAL/CLOTHBOUND NOTEBOOK TO BE HANDED IN. Photocopy reaction trees and highlight the areas relevant to your unknowns. Create and complete tables of reaction step, reagent, and equation from your notes. Identify the unknowns.
LAB #10 REDOX STANDARDIZATION LAB #35.
A titration of a KMnO4 solution will be used to standardize the KMnO4 solution.
The data and results of this lab will be kept for the REDOX ANALYSIS LAB #11.
Unknown oxalate samples will be titrated with the standardized KMnO4 solution.
A mass % of oxalate calculation will be used like the Asprin Analysis LAB #5.
