Imagine that you need to perform UV-Vis spectroscopy on solutions of naphthalene. Specifically, you need to...
Imagine that you need to perform UV-Vis spectroscopy on solutions of naphthalene. Specifically, you need to determine what molar concentration of naphthalene in a transparent solvent would allow 5% of 315 nm light to pass through a 0.5 cm cuvette. The molar extinction coefficient of naphthalene at 315 nm is 320 M−1 cm−1. Which of the following choices represents the desired concentration of naphthalene? Hint: recall the Beer-Lambert equation and the relationship between absorbance and transmittance.
Answer choices:
| 0.008 M |
| 0.006 M |
| 0.032 M |
| 0.010 M |
| 0.50 M |
| 0.012 M |
Homework Answers
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Hi, I need help with answering these questions. Thank you.
1) What is the molar absorptivity of riboflavin (with units)?
Assume that the cuvette has a pathlength of 1.00 cm and that the
blank had an absorbance of 0.00.
2. If a sample of riboflavin with an unknown concentration had
an absorbance of 0.597, what is the concentration of the
sample?
3. A sample of riboflavin is prepared by crushing 5 tablets and
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I
need help doing just the questions, not the graph or the
conclusion
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