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Typical results are shown for the absorbance of [ Ti ( H 2 O ) 6 ] 3 + size 12{ \[ "Ti" \( H rSub { size 8{2} } O \) rSub { size 8{6} } \] rSup { size 8{3+{}} } } {} measured at 490 nm.

Concentration (mg/mL) %Transmittance Absorbance
0 100. 0
1 50.0 0.301
2 25.0 0.602
3 12.5 0.903

Over the studied range the solutions obey Beer's Law. If a solution has a measured absorbance of 0.450, we can calculate its concentration to be 1.5 mg/mL.

Experimental procedure

In this experiment, each lab pair will measure the absorbance of CuSO 4 size 12{"CuSO" rSub { size 8{4} } } {} at six concentrations. You will create a calibration curve to correlate copper sulfate concentration to absorbance. This curve will be used next week to determine the concentration of an unknown copper sulfate solution and, in turn, the percent yield of a series of chemical reactions.

Materials CuSO 4 5H 2 O size 12{"CuSO" rSub { size 8{4} } cdot "5H" rSub { size 8{2} } O} {} distilled water pipette bulb 1cm cuvette 4 - 25 mL volumetric flask for your dilutions

Note: You will be borrowing these and must collect them from your TA. Do not forget to return the flask at the end of the lab). All students will lose 3 points in that lab section if any go missing!

100 mL volumetric flask for the parent solution (in your drawer)10 mL volumetric pipette or 10 mL graduated cylinder

  • Measure out an appropriate mass of CuSO 4 5H 2 O size 12{"CuSO" rSub { size 8{4} } cdot "5H" rSub { size 8{2} } O} {} to get 100ml of ~0.1M solution and record the mass on your report form. Show your calculation to the TA before making the solution. This is your parent solution. Calculate the molarity using the actual mass measured and record it.
  • Do the following dilutions and calculate the concentrations for each.
Dilution (ml parent : ml total)
0:25 (DI H 2 O size 12{H rSub { size 8{2} } O} {} )
25:25 (parent solution)
  • Measure the absorbance of the 6 solutions you have prepared and the unknown given to you by your TA.


Plot the concentration as a function of absorbance for your six solutions. Perform a linear regression analysis and determine the equation of a best-fit line.

Prelab: spectrophotometry and data analysis–Beer’S law

Hopefully here for the Pre-Lab

Name(Print then sign): ___________________________________________________

Lab Day: ___________________Section: ________TA__________________________

This assignment must be completed individually and turned in to your TA at the beginning of lab. You will not be allowed to begin the lab until you have completed this assignment.

In many of the experiments that you will do throughout the duration of this course you will be asked to analyze your data by making plots and calculating the best fit line through your data. One program commonly used to analyze data in this fashion is Microsoft Excel®. The following exercise will help you through the process used to obtain a plot and linear regression for a set of data.

Suppose you go for a 5 mile run and you tabulate the after each mile as in the following table.

Distance Traveled (miles) Time (sec)
1 510
2 1026
3 1548
4 2077
5 2612


  • Plot the distance traveled in miles vs. the time in seconds.
  • Use linear regression to obtain a trendline and give the equation obtained in terms of the variables distance traveled and time and the R-squared value. Comment on the meaning of the R-squared value and its significance when doing data analysis.
  • Using the equation you obtained by doing linear regression, estimate how long the 6th mile will take you to run.
  • Assuming this linear trend persists, how far have you run if you finish in 2900 sec.


  • In order to plot this data in excel, you should enter the data exactly as above in to column A (rows 1-6) and column B (rows 1-6).
  • To plot the data you will need to go to Insert on the tool bar and then click Chart. A Chart Wizard will appear. Select XY(Scatter) as the Chart type and choose the sub-type that does not have any lines connecting the points, then click next.
  • On Step 2, click on the series tab near the top of the screen and click Add.
  • You do not need to name the series unless you have multiple plots on one graph, but you can type in a name if you wish.
  • To insert the X data, click on the icon at the far left of the x series box.
  • Select the x values by clicking on the first one and while the left mouse button is down dragging the mouse down to the last value.
  • When the values have been selected click the icon again and repeat for the y values. You may also manually enter the values by separating them with a comma. Don’t forget you need to remember what units you are using when answering questions.
  • Click next when you have x and y values entered correctly.
  • The next step is just entering title information and changing the appearance of your plot; click next when finished.
  • Choose your chart location and then finish. You now need to place a linear regression line on your plot.
  • Right click on a data point and pick add trendline.
  • Choose linear as the type and click the options tab.
  • Check the boxes to get the equation and R-squared value and click ok.

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Honors chemistry lab fall. OpenStax CNX. Nov 15, 2007 Download for free at http://cnx.org/content/col10456/1.16
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