A calibration plot for a particular absorbing species is constructed according to Beer-lambert's law and the equation of the best-fit straight line is y= 10.86x. What is the concentration of a solution of the same species if its absorbance is measured to be 0.489

A protein’s concentration can be determined spectrophotometrically by mixing it with an indicator called a Bradford reagent and measuring the amount of light absorbed by the protein. Use the plot below to determine the mass of protein (in micrograms, μμg ) in 100.0 mL of the solution if its absorbance is 0.398. A.  52 B.  3.1 C.  2.4 D.  0.52 E.  0.031

Spectroscopy relies on the excitation and relaxation of electrons. Which of the following statements about spectroscopy is true? Phosphorescence is the emission of a photon of light as an electron transitions from the excited singlet state to ground state. Collisional deactivation of an excited molecule decreases the absorbance response. Molecular absorption spectrometry measures the change in light intensity as light passes through a sample. Fluorescence is the absorption of a photon of light as an electron transitions from the ground state to an excited triplet state.

The spectra that you observe are for approximately 1 x 1012 atoms. So it is likely, that with electronic excitation, many of the electronic energy levels will be readily populated. However, the higher energy levels will be less populated, so what does say about the intensity of the higher energy peaks? Is that observation consistent with the spectrum we measured with the spectrometer?

If the absorbance of 0.244 M copper (II) chloride solution is 0.534 and the path length of light is 1.00 cm, what is the Beer's Law extinction coefficient, epsilon?

9. Absorption spectra for molecules are more complex than atomic spectra because: C (a) Molecular species have side reactions C (b) Atomic species do not absorb light C (c) The number of energy states of molecules is enormous when compared with the number of energy states for isolated atoms. 10 absorption / emission of light by a molecule and describe the processes in terms of energy levels. How this information can be used for obtaining analytical information on an analyte of interest? Explain the phenomenon of

If a solution has an absorbance value of 0.325 at a wavelength of 450 nm, what is the percent transmittance of this solution at this wavelength?

8. This question has two parts a. and b. a. Using the information provided below, derive an expression to show that the energy of an electronic transition measured from UV-VIS spectroscopy is a function of the wavelength of the light absorbed using the equations below. Make sure you indicate your final answer! γλ = c AE = hv where Eis the energy for the transition, v is the frequency of light, A is the wavelength, c and hare the speed of light and Plank's constant respectively (both constants). Insert an image (.jpeg, png, .heic) showing all of your work for deriving the expression in the box below.

6. Sketch a Jablonski diagram that illustrates the absorbance of a photon by a chemical species and illustrates the fates of the chemical species after that photon absorption. Please label all transitions appropriately and indicate a time scale for each transition.

What photon energy and wavelength would you need to send on a compound havingan energy gap (Eg) of 2.7 eV? Detail your answer with appropriate information.