Pasport PS-2121 Quick Start Manual

Colorimeter

PS-2121

cuvette

lid

cuvette holder

Calibration
button

CARD 1A

Colorimeter Quick Start

The PS-2121 Colorimeter measures the transmittance (%) of different colors of
light through a solution, and can be used to determine a solution’s concentration.

Equipment Setup

1. Connect a PASPORTTM interface to a USB port on your computer or to a USB hub.
(If using an Xplorer, connect the Xplorer cable to a USB port on your computer.)

2. Connect the sensor to the PASPORT interface (USB Link, PowerLink, Xplorer, etc.).

3. The software launches when it detects a PASPORT
the PASPORTAL window.

sensor. Select a choice from

Equipment equipment needed:

• PASPORT interface with USB-compatible computer or Xplorer (PS-2000)

• DataStudio

®

, DataStudio Lite, or EZscreen software

®

800-772-8700 • 916-786-3800 • [e-mail] • www.pasco.com

Colorimeter Specifications

Specifications:

Range:

Wavelengths:

Accuracy:

Resolution:

Default sample rate

Maximum sample rate:*

Temp. Range:**

0 to 100% transmittance

Red (660 nm), orange (610 nm),
green (565 nm), blue (468 nm)

±

0.5% transmittance

0.1% transmittance

1 sample/sec

5 samples/sec

5–40°C (recommended)

1

3

2

012-08158C

CARD 1B

Colorimeter Usage Tips

* The recommended sample rate is 1 Hz for color and Beer’s law studies.

If you plan to do reaction order studies, use a faster sample rate.

**The temperature range applies to both the temperature of the solution in

the cuvette and the ambient temperature. Using the Colorimeter above
or below the recommended range or with condensation may give false
readings.

Activity: Transmittance and
Absorbance of Colors in Solution

CARD 2A

Equipment Required: PS-2121 Colorimeter, DataStudio or DataStudio Lite,

PASPORT
red (or other) food coloring, 2 cuvettes

1. Fill one cuvette with distilled water and screw the cap on securely.

2. Fill another cuvette with colored solution (i.e. 2 drops of red food coloring

3. Insert the cuvette containing distilled water into the cuvette holder and

4. Plug the Colorimeter into the PASPORT interface, launch DataStudio,

5. Open the Colorimeter lid, remove the first cuvette, and replace it with the

™ interface connected to a USB-compatible computer, distilled water,

and 6 ml of water). Screw on the cap, then gently rock the cuvette back
and forth to evenly mix the solution without creating bubbles.

tightly close the lid.

and click the Start button to begin collecting data. The default graph
displays the transmittance readings for each of the four possible
wavelength settings. Click the Stop button to end data collection.

cuvette containing the colored solution. Repeat steps 3 and 4 to collect
data for the colored solution.

®

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Activity Example (Continued): Sample Results

Transmittance of Colors through a Red Solution

6. Examine the graph display from run #2 (the colored solution). Note
the transmittance readings at each wavelength setting. How do
they differ from transmittance readings for the distilled water?

7. To view absorbance data, click on the button to open the

PASPORT Setup window. Maximize the PASPORT Setup window
to view the Colorimeter options.

8. Uncheck each of the four transmittance boxes, and click to place an

“X” next to each of the four absorbance boxes. (Note the changed
“Data” list in the Summary bar to the left.) Close the Setup window.

9. To open a new Graph display, double click on the Graph icon in

the Data list. When the dialog box appears, select a data source to
display absorbance for a data run and wavelength. Click OK to
open Graph 2, which will display Absorbance vs. Time. (Note: If
desired, you can use a Digits display instead of a Graph.)

10. To compare absorbance values for the distilled water and colored

solution, drag the appropriate icons from the Data list to Graph 2.
Analyze which colors were absorbed or transmitted for each run
and explain your results.

012-08158C

CARD 2B

Viewing Results in DataStudio

Note: Only the first data run of all four colors (red, blue, green,
orange) will correspond to the graph colors that DataStudio
displays. (This applies to either default measurements or the first
four chosen in the PASPORT Setup window).

DataStudio/DS Lite

View transmittance or
absorbance results:

Open the Experiment
Setup window:

Set up the Colorimeter
to read absorbance:

View a linear fit*:

Procedure

From the Data list, drag a colored Transmittance or
Absorbance icon to a Graph or other display.

On the main toolbar, click on the Setup button to
open the Experiment Setup window.

In the upper right corner of the Experiment Setup
window, click on the Maximize button. Scroll to the
Colorimeter box and check the absorbance boxes.

Click on the Fit menu button. From the Fit menu,
select “Linear Fit.”

*To calculate the log or inverse of absorbance, create an equation using the

DataStudio Calculator. The linear fit and Calculator features are not available
in DataStudio Lite.