Problems
14.1 Write Beer’s law and define all of the terms.
14.2 What is the frequency of light with a wavelength of (a) 1 nm, (b) 500 nm, and (c) 3 cm?
Give the spectral classification of the radiation of each frequency.
14.3 What is the wavelength of light with a frequency of (a) 10^18 Hz, (b) 10^6 Hz, and (c) 10^12 Hz.
Give the spectral classification of the radiation of each wavelength.
14.4 A 0.1% solution of lysozyme gives an absorption of 2.7 at 280 nm. (a) If the concentration
is 0.01%, what absorption would be measured? (b) If an absorbance of 1.0 is measured,
what is the concentration?
14.5 Adenosine 5′-phosphate has an extinction coefficient of 1.54 × 104 M−^1 cm−^1 at 260 nm.
(a) If the concentration of the sample is 1μM, what absorbance would be measured in a
1-cm cuvette? (b) If an absorbance of 0.1 is measured, what is the concentration?
14.6 If the extinction coefficient of a molecule is 1000 M−^1 cm−^1 and you measure an absorption
of 0.1 in a 1-cm cuvette, what is the concentration of the molecule?
CHAPTER 14 OPTICAL SPECTROSCOPY 315
and then cleaving the site. By labeling different ends of the DNA it is pos-
sible to get profiles for the distances between the two ends as a function
of parameters such as the enzyme concentration, and to derive possible
models for the arrangement of the enzyme on the DNA strands.
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