(12) Which one of the following statements about fluo-rometry is FALSE?a) Fluorescence is better detected at 90 from the exci-tation direction.b) Fluorescence is typically shifted to longer wave-length from the excitation wavelength.c) For most fluorescent compounds, radiation is pro-duced by atransition

Answered: Image /qna-images/answer/7d803c8e-eab4-4906-9454-82e3c6f0a10b.jpg

Answered: (12) Which one of the following…

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 6P

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Which of the following statements concerning spectroscopy is correct? A) Concentration of a solution is directly proportional to the % of photons transmitted. B) Salt plates are often used in IR spectroscopic measurements because they are transparent in that region. C) Molar absorptivity is a constant for given species, regardless of concentration or wavelength. D) Fluorescence excitation is usually red-shifted from emission wavelength. E) 2 or more statements are correct. The absorbed energy to enable vibrational level transition falls within which wavelength range A) radio wave B) microwave C) IR D) X-ray E) UV and visible
Topic: Determination of Calcium by Atomic Absorption Spectroscopy (AAS) Answer this: 1. It is observed that as you increase the concentration of the standard, the intensity of yellow flame also increases. Why?
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Find information on fluorescent dye Fluo-3: Display its structure Briefly describe its purpose and the mechanism of operation Display its fluorescence spectra Display transmission spectra of commercially available optical filters required for flow cytometry measurements of cells stained with Fluo-3 (see lecture notes on where to look)
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Q1 (a) Explain how the peaks in Infra-Red spectroscopy are generated and what information the peaks can provide about the molecule analysed.(250 words limit) 25% (b) Explain how interaction of Ultra-Violet / Visible light with a molecule produces an absorbance and hence a peak, indicating what parts of a molecule can absorb this radiation. (250 words limit) (25%)
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Which of the following is NOT true about infrared spectroscopy? (a) when molecules absorb IR bonds start vibrating with greater amplitude (b) when molecules absorb IR electrons jump to higher energy levels (c) polar bonds show greater IR absorbances than non-polar bonds (d) IR radiation is lower in energy than uv radiation

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