# Spectroscopy – Section 1

1. Molar absorbtivities of compounds exhibiting charge transfer absorption are

A. small
B. moderate
C. large
D. none of these

2. Molar absorbtivity is the measure of the

A. amount of light absorbed per unit length
B. amount of light absorbed per unit concentration
C. amount of light reflected and absorbed per unit concentration
D. None of the above

Correct Answer: B. amount of light absorbed per unit concentration

3. Which of the following relationships between absorbance and %transmittance is incorrect?

A. A = log10 100 / %T
B. A = 2 – log10 %T
C. A = log10 1 / T
D. All are correct

Correct Answer: C. A = log10 1 / T

4. Why is it generally preferable to use absorbance as a measure of absorption rather than % transmittance?

A. Because %T cannot be measured as accurately as absorbance
B. Because %T is dependant on the power of the incident radiation
C. Because absorbance is proportional to the concentration of the analyte, whereas %T is not
D. none of the above

Correct Answer: C. Because absorbance is proportional to the concentration of the analyte, whereas %T is not

5. In the past, IR spectra had to be acquired one wavelength at a time, which took a long time. Today quick spectra is due to the

A. the Fourier Transfer Algorithm allows us to scan all frequencies at once
B. light is faster today that it used to be
C. absence of broad spectrum of wavelength
D. none of the above

Correct Answer: A. the Fourier Transfer Algorithm allows us to scan all frequencies at once