Using The Product With Spectral Analysis - Vernier Go Direct UV-VIS Manual

Using the Product with Spectral Analysis

Connect the sensor following the steps in the Getting Started section of this user
manual.
Select the Type of Data to Measure
The three options for Experiment Types are
1. Measurement vs. Wavelength—collect a full spectrum.
2. Measurement vs. Concentration—conduct a Beer's law experiment.
3. Measurement vs. Time—collect time-based data for a kinetics experiment.
By default, Absorbance is expanded. You can also choose from % Transmittance,
Emissions, or Advanced Full Spectrum. Use the Advanced Full Spectrum mode to
switch among all the measurement types in the same session. For complete
instructions, refer to the Spectral Analysis user manual at
www.vernier.com/spectral-analysis
Measurement vs. Wavelength (Full Spectrum)
1. Select Measurement vs. Wavelength.
2. If applicable, follow instructions for calibration. Align the cuvette so the clear
side of the cuvette is facing the light source. Note: Calibration is not required
for emissions.
3. You are now ready to collect data. Fill a cuvette about 3/4 full of a sample of
the solution to be tested. Place the sample in the Spectrophotometer and click
or tap Collect. Click or tap Stop to end data collection. The spectrum is
automatically stored.
4. Save or export your data from the File menu.
Measurement vs. Concentration (Beer's law)
1. Select Measurement vs. Concentration.
2. If applicable, follow instructions for calibration. Align the cuvette so the clear
side of the cuvette is facing the light source. Note: Calibration is not required
for emissions.
3. Follow the instructions in the Choose a Wavelength dialog box. Select Done.
4. Click or tap Collect. Your first sample should still be in the
Spectrophotometer. After the reading stabilizes, click or tap Keep. Enter the
concentration of the sample and click or tap Keep Point.
5. Place your second sample in the cuvette slot. After the reading stabilizes, click
or tap Keep. Enter the concentration of the sample and click or tap Keep Point.
6. Repeat the previous step for the remaining samples. When finished, click or
tap Stop to end data collection. The data are automatically stored.
7. To see the best fit line equation for the standard solutions, click or tap Graph
Tools, select Apply Curve Fit, and choose Linear. Click or tap Apply.
8. If doing Beer's law to determine the concentration of an unknown, place the
unknown sample in the cuvette holder. Click or tap Graph Tools and enable
Interpolate. Click or tap along the line until you find the concentration value
that matches your unknown's measurement.
9. Save or export your data from the File menu.
Measurement vs. Time (Kinetics)
1. Select Measurement vs. Time.
2. If applicable, follow instructions for calibration. Align the cuvette so the clear
side of the cuvette is facing the light source. Note: Calibration is not required
for emissions.
3. Follow the instructions in the Choose a Wavelength dialog box. Select Done.
4. The default data-collection settings collect measurements every two seconds
until the user manually stops data collection.
5. Mix the reactants. Transfer ~2 mL of the reaction mixture to a cuvette and
place the cuvette in the spectrometer. Click or tap Collect.
6. When finished, click or tap Stop.
7. To fit a function to the data, click or tap Graph Tools, select Apply Curve Fit,
and choose the appropriate curve fit. Click or tap Apply.
8. To add a calculated column to the data set, click or tap Column Options in the
measurement header on the data table. Select Add Calculated Column. Modify
the name, units, and displayed precision accordingly. Select Insert Expression
and select the appropriate equation. Modify the parameters and column
options, if necessary. Click or tap Apply. The calculated column is
automatically displayed on the graph.
9. Save or export your data from the File menu. To modify the data that are
displayed on the graph, click or tap on the appropriate axis label.
Change the Settings in Spectral Analysis
1. Click or tap the gear to show the Spectrometer Settings dialog.
2. There are three parameters listed in the dialog box:
Integration Time: This is similar to the shutter speed of a camera.
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Spectral Analysis automatically selects the proper sample time during
calibration in Absorbance and % Transmittance modes. If using Emissions
or Advanced Experiment modes, you can modify this value to increase the
amount of light hitting the detector and the signal spectral output.
Wavelength Smoothing: This is the number of adjacent readings on either
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side of a given value that is used to calculate an average value.
Temporal Averaging: This is the number of readings taken at a given
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wavelength to calculate an average reading.
3. Select the Calibrate button to recalibrate your spectrometer at any time.
Measure an Emission Spectrum with Spectral Analysis
You may use your Spectrophotometer to measure the visible emission spectrum of
a light source such as an LED or a gas discharge tube. To do so, you will need to
purchase the Vernier Optical Fiber (order code: VSP-FIBER).
Measure Intensity of Light Emissions
Insert the Vernier Optical Fiber into the spectrometer.
1. Connect the spectrometer following the steps in the Getting Started section of
this user manual.
2. Launch Spectral Analysis.
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