(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

See similar textbooks

Similar questions

10. a. Light at 278 nm passes through protein RNase A with optical path length is 1μm and the concentration of protein RNase A is 0.5 M. If the absorbance is 0.5, what is the absorptivity in M-1 cm-1? b) What is the corresponding transmittance?
Covalent bonds in a molecule absorb radiation in the IR region and vibrate at characteristic frequencies. (a) The C---O bond absorbs radiation of wavelength 9.6 mm. What frequency (in s-1) corresponds to that wavelength? (b) The H---Cl bond has a frequency of vibration of 8.652x1013 Hz. What wavelength (in mm) corresponds to that frequency?
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?
Specific absorbance is the absorbance of a 1% solution of a given substance. The specific absorbance can be calculated by: A 1% ст C(i % , For the identification of a substance, 0.0482 g of substance has been weighed, which has been dissolved in 50.00 ml of demineralized water. Thereafter, 50.0 µl of this solution has been diluted to 50.00 ml. a UV-wise analysis (A = 249 nm) of this dilution gave an absorbance of 0.925. a) Calculate the concentration of the diluted solution in% (w/v). b) Calculate the specific absorbance of the substance. c) Will it be possible to measure the specific absorbance directly on a 1% solution? Why / why not?
(d) The Beer-Lambert law states that the absorbance (A) of light by a solution in a cuvette is given by: 10 A = In == ECL where lo is the incident light intensity, is the transmitted light intensity, e is the molar absorptivity, c is the concentration of the solution, and L is the path length of the cuvette. (1) Light with a wavelength of 800 nm is passed through a cuvette containing a solution of Coumarin dye. After passing through the cuvette, the light intensity was reduced to 10% of its initial value. What is the absorbance of the solution of Coumarin dye? (ii) The concentration of the Coumarin dye is 0.004 mol dm3, and the cuvette has a path length of 1 cm. What is the molar absorptivity of Coumarin dye at 800 nm, in units of m² mot¹? (IT) The molar absorptivity of Coumarin dye at 400 nm is three times larger than at 800 nm. How would the absorbance of the solution change, when measured with 400 nm light rather than 800 nm light?
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)
12) Chemical Formula: C9H20O IR: strong broad 3300cm-1 1H 9x2=18+2=20-20=0 1H 3 PPM −2 18H 0
(d) The Beer-Lambert law states that the absorbance (A) of light by a solution in a cuvette is given by. A = ID==ecL In=-= where lo is the incident light intensity, / is the transmitted light intensity, e is the molar absorptivity, c is the concentration of the solution, and Lis the path length of the cuvette. (1) Light with a wavelength of 800 nm is passed through a cuvette containing a solution of Coumarin dye. After passing through the cuvette, the light intensity was reduced to 10% of its initial value. What is the absorbance of the solution of Coumarin dye? (1) The concentration of the Coumarin dye is 0.004 mol dm3, and the cuvette has a path length of 1 cm. What is the molar absorptivity of Coumarin dye at 800 nm, in units of m² mot¹?
A carbon is covalently attached to =O, -CH2-CH3, and -CH3. It is best called a(n): aldehyde fatty acid ketone carbohydrate alcohol amino acid The movement of low-density lipoprotein (LDL) particles into our body cells from the bloodstream occurs by: passive transport a channel protein facilitated diffusion active transport exocytosis Chlorophyll fluorescence occurs when electrons are unable to move forward in the reactions of photosynthesis because the reactions are slowing down. Which of the following would be likely to cause an increase in chlorophyll fluorescence, i.e. by slowing down photosynthesis? choose one or more, or none 1-making more thylakoid membranes in chloroplasts 2-giving chloroplasts access to more CO2 3-raising the pH of the thylakoid spaces
3. Regions of the electromagnetic (e/m) spectrum and corresponding molecular processes. (a) Sketch the e/m spectrum like depicted in figure below. For your sketch, use the following units (all together in one plot): wavelength, frequency, wavenumbers, and energy. (b) What are the molecular processes that can be studied by the different types of e/m radiation? Name three (3) processes. (A) Radio waves (B) Micro- waves (C) (D) Infrared Visible radiation light Ultraviolet m X-rays (F) Gamma-rays
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

SEE MORE QUESTIONS

Recommended textbooks for you

Principles of Modern Chemistry

Chemistry

ISBN:

9781305079113

Author:

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

Publisher:

Cengage Learning

Chemistry In Focus

Chemistry

ISBN:

9781337399692

Author:

Tro, Nivaldo J.

Publisher:

Cengage Learning,

Macroscale and Microscale Organic Experiments

Chemistry

ISBN:

9781305577190

Author:

Kenneth L. Williamson, Katherine M. Masters

Publisher:

Brooks Cole

Principles of Modern Chemistry

Chemistry

ISBN:

9781305079113

Author:

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

Publisher:

Cengage Learning

Chemistry In Focus

Chemistry

ISBN:

9781337399692

Author:

Tro, Nivaldo J.

Publisher:

Cengage Learning,

Macroscale and Microscale Organic Experiments

Chemistry

ISBN:

9781305577190

Author:

Kenneth L. Williamson, Katherine M. Masters

Publisher:

Brooks Cole

Principles of Instrumental Analysis

Chemistry

ISBN:

9781305577213

Author:

Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS