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Spectrophotometers can be used to measure the absorbance of light of a particular wavelength by a certain material. BRIEFLY explain what is meant by the term absorbance.
How much light is absorbed by a solution
100
What is Beer’s Law? & what is Lambert’s Law?
Beers law is ""there is a directly proportional relationship between absorbance and concentration" Lamberts law is "as pathlength increases, transmittance decreases and absorbance increases"
100
What is the combined Lambert-Beer Law? and what do the units stand for?
A=ËCL a = absorbance Ë= absorptive constant C = concentration (M) L = pathlength
100
Is it more convenient to use Absorbance or Transmittance to determine the concentration of a substance?
Absorbance as it is a directly proportional relationship. Transmittance require a log of equation.
100
Why is the selection of optimal analytical wavelength important for spectrophotometric measurement? (Hint, material to be discussed in Week 12 practical may assist you to answer this).
You select the optimal wavelength for your solutions absorbance
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Why is the selection and use of an appropriate Blank important for spectrophotometric measurement? (Hint, material to be discussed in the Week 12 practical may assist you to answer this)
Have a blank and a sample. Sample includes everything that you are measuring (unknown), the blank has everything (except the unknown) so when you get both the absorbance values, you can take away the blank from the sample
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