A spectrophotometer can be set to measure % transmittance and/or absorbance over a wide range of wavelengths. Our Colorimeter can only measure four specific wavelengths produced by internal LEDs. The Colorimeter costs far less, but works for a more limited variety of experiments.
For a given set of liquid solutions, a spectrometer and our Colorimeter will report different absolute absorbance values. However, many of the same experiments can be done on either device and valid results can be obtained on both devices. For example, if you are doing an experiment based on Beer's law (absorbance vs. concentration), both devices will give you a direct relationship between the absorbance value and the concentration of the standard solutions. Subsequent determination of an unknown solution based on the standards will produce similar results. Kinetics data can also be collected with a spectrometer or Colorimeter.
A spectrometer can measure a full absorbance (or % Transmittance) spectrum, which is important for many of the AP Chemistry lab experiments from the College Board. Our lab book, Vernier Chemistry Investigations for Use with AP* Chemistry, order code APCHEM, $48, contains 16 inquiry-based laboratory experiments and is written to be used with a spectrometer.
For a brief comparison, check out the Tech Tip at https://www.vernier.com/products/packages/chem-i/gdx/
To learn more about spectrometers, see https://www.vernier.com/products/sensors/spectrometers/
* AP and Advanced Placement Program are registered trademarks of the College Entrance Examination Board, which was not involved in the production of and does not endorse this product.
TIL 1577: Do you have labs written for your spectrophotometers?
TIL 2179: What is the difference between the V-SPEC and the GDX-SVISPL? Why does one cost so much more than the other?
TIL 2569: Why don't all of my spectrometers and/or Colorimeters read the same absorbance value for the same sample?