Question

Question 8: How can you use absorption spectra of dye standards to identify the dye(s) present in a sample? Can you identify the dyes that make up a mixture? Explain briefly in a sentence or two. Question 9: How can you use the absorption data for a dye standard of unknown concentration to determine the concentration of dye in an unknown sample? Explain briefly in a sentence or two. Question 10: How can you accurately prepare very low concentration standards in the laboratory? Explain briefly in a sentence or two.

Answer 1

8. Absorption spectrum of unknown dye is compared with the spectrum of known compound. If both the spectra matches then we can find the unknown dye sample.

9. From the absorption spectrum we can find the concentration by using Lambert beers law which relates the absorbance of sample with the concentration

A= ecl

Where, A= absorbance

e= molar absorptivity

c= concentration

l = Path length

10. Weighing accurate amount of sample in necessary for carrying out the preparation of very low concentration standards in laboratory.