Determine the Concentr
Determine the Concentration of a Solution
ation of a Solution
Determine the concentration of a solution by plotting absorbance
versus concentration.
1. Prepare the samples for analysis.
a. Fill the cuvettes ¾ full with the sample solutions and cap.
b. Prepare a reference solution by filling one cuvette ¾ full with
the solvent used to make the sample solutions.
2. Connect the Spectrometer to Spectrometry.
3. Calibrate the spectrometer.
a. Select the Analyze Solution page
.
b. Cover the spectrometer to block ambient light and click
Calibrate Dark
.
c. Insert the reference solution in the spectrometer then click
Calibrate Reference
.
4. Select an Analysis Wavelength.
a. Place the most concentrated solution to be analyzed into the
spectrometer then click Record
.
b. Use the Tools to adjust the smoothing and number of scans
to average as needed.
c. Click Stop
when you are satisfied with the results.
d. Drag the coordinate tool on the graph to the wavelength you
want to analyze. This is usually a high point on the curve.
e. Once you have found a desirable wavelength click
.
5. Collect Data.
a. Select analyze Concentration from the menu at the top of the
screen. A table will appear on the left side of the screen that
has columns for Concentration and Absorbance.
b. Select the concentration cells in the column titled
Concentration and type over the given values with the
concentrations of the samples prepared.
c. Select Record to start analyzing the solution.
d. Place the highest-concentration sample into the spectrometer
and click the cell in the Absorbance column that corresponds
to the respective concentration. Once the absorbance
stabilizes click
next to the absorbance to record the value.
Note: A value of three indicates that the solution is too
concentrated for the selected wavelength.
e. Repeat the previous step for the samples of lesser
concentration and record their absorbance values.
f. Click Stop to stop data collection.
6. Analyze Data.
a. Click to remove the Live Scan Display from the graph.
b. Click Scale to Fit to rescale your data.
c. Click Linear Fit to create a best fit line and display the
equation for the line.
d. Place the cuvette containing a solution of unknown
concentration into the spectrometer.
e. Select the Absorbance
Absorbance cell in the Determine Unknown
Determine Unknown
Concentration
Concentration table at the bottom of the screen.
f. Click Record to start analyzing the solution.
g. Once the absorbance stabilizes click
next to the
absorbance to record the value.
h. Click Stop to stop data collection.
i. Use either the graph or the equation of the line to determine
the unknown concentration. Select the Concentration cell and
enter the concentration.
Determine Reaction Rate and Or
Determine Reaction Rate and Order
der
Determine reaction rate and order by plotting absorbance versus
time.
1. Prepare the samples for analysis.
a. Fill the cuvettes ¾ full with the sample solutions and cap.
b. Prepare a reference solution by filling one cuvette ¾ full with
the solvent used to make the sample solutions.
2. Connect the Spectrometer to Spectrometry.
3. Calibrate the spectrometer.
a. Select the Analyze Solution page
.
b. Cover the spectrometer to block ambient light and click
Calibrate Dark
.
c. Insert the reference solution in the spectrometer then click
Calibrate Reference
.
4. Select an Analysis Wavelength.
a. Place the most concentrated solution to be analyzed into the
spectrometer then click Record
.
b. Use the Tools to adjust the smoothing and number of scans
to average as needed.
c. Click Stop
when you are satisfied with the results.
d. Drag the coordinate tool on the graph to the wavelength you
want to analyze. This is usually a high point on the curve.
e. Once you have found a desirable wavelength click
.
5. Collect Data.
a. Select analyze over Time
from the top of the screen.
b. Place the sample solution into the spectrometer and click
Record
.
c. Click Scale to Fit
to rescale your data. After allowing
enough time for the reaction to take place, click Stop
.
6. Analyze Data.
a. Click to remove the Live Scan Display from the graph.
b. Click Linear Fit to create a best fit line and display the
equation for the line.
c. Click Quick Calcs on the
y-axis to cycle the between
Absorbance, ln (Absorbance), and 1/Absorbance to find a
linear trend. Use the results to determine the order of
reaction.
UV-VIS Spectrometer | SE-3607
Product Guide
3
012-16942A
