This is concerning a spectrophotometer exercise. We used two different sized test tube cuvettes. One was...
This is concerning a spectrophotometer exercise.
We used two different sized test tube cuvettes. One was taller/larger; one was shorter/smaller. We filled each cuvette with the same solution. However, the taller cuvette had an absorbance reading of .108, while the shorter cuvette had a reading of .131.
Why did I obtain different readings for the same solution when read in different-sized cuvettes?
Thank you.
Homework Answers
From the Beer's Law: A=εbC, we can say that the abosrbance (A) of a particular solution is dependent on its path length (b), molar absorptivity(ε) and concentration (C) of the solution.
A sample is usually taken in a cuvette which is placed in a spectrophotometer for the measurement of the optical density (O.D). The width of the cuvette determines the path length (b) of the light through the sample, therefore if the size of the cuvette used to measure the O.D of a same sample is different then it will affect the calculation of the absorbance of the solution.
Add Answer to:
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We used two different sized test tube cuvettes. One was...
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