In some IR spectra appearing in research articles, the bands have their base at the bottom of the graph and the peaks at the top (like stalagmites); however, in other spectra the bands appear "inverted" (stalactites). Only one of the following is an acceptable explanation.(A). "Inverted" spectra have negative absorbances because the absorptivity coefficient of the species of which the spectrum is recorded is negative(B). It depends on the optical configuration of the instrument: in some equipment the monochromator is between the source and the sample and in others between the sample and the detector(C). Some spectra are transmittance and others are absorbance(D). Everything depends on the number of lenses in the equipment's optics; if this number is odd, the spectrum comes out inverted

What color would you expect for light transmitted through a solution with an absorption maximum at (a) 450; (b) 550; (c) 650 nm?

(a) Three components in a mixture have varying distribution constants between the mobile phase and the stationary phase. One of the components has a very high distribution constant. Would this component likely elute first or last and how would you design an experiment or modify the components of the separation to make it perform in the opposite manner? (b) One way to dramatically increase the sensitivity of a quadrupole mass spectrometer is to use a technique called selected ion monitoring (SIM).  Explain how this technique works and why it improves sensitivity. Explain what dwell time means. Be sure to draw a diagram and describe how this analysis scheme works. Also, is there a compromise between a wide range of masses scanned and SIM? Explain in easy details.

An aqueous solution of a triphosphate derivative of molar mass 502 g mol-1, was prepared by dissolving 17.2 mg in enough water to make 500 cm3 of solution and a sample was transferred to a cell of length 1.00 em. The absorbance was measured as 1.011. Calculate (a) the molar absorption coefficient;(b) the transmittance. expressed as a percentage.for a solution of twice the concentration.

Assume for the following situations that Beer’s law remains linear. For (a) and (b), indicate whether the extinction coefficient ε, path length b, or concentration C is changing, and how it will change the absorbance of the solution. (a) A sample is moved from a test tube that is 1.0cm wide to a test tube that is 1.5cm wide. (b)  A sample is diluted by adding enough solvent to double its volume. (c)  A solution of iron (III) chloride appears brown when in high enough concentrations. In a 1.0 cm cuvet, the absorbance of 334 nm light by a 5.4 × 10−4 M solution of FeCl3 is measured to be 1.05. What is the extinction coefficient of the FeCl3 complex at this wavelength? (d)  A sample containing an unknown concentration of FeCl3 is measured to have an ab- sorbance of 0.43 at 334 nm in a 1.0 cm cuvet. What is the molar concentration of the solution?

An ethanol solution of 3.5 mg/100 ml of compound Y (150.0 g/mol) in a 1.00 cm quartz cell has an extinction coefficient (ɛ) of 23,150 at Amax=235 nm. What is the expected absorption (A)? Report your answer to the correct number of significant figures.,

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A solution in part C initially contains (4.2100x10^-4) molar SCN¯ and (3.1700x10^-3) molar Fe3+ This solution was then measured using the colorimeter, and an absorbance of (5.01x10^-1) was recorded.The constant determined in part A of the experiment was found to be (3.4800x10^3). Using the data provided above, determine the equilibrium concentration of Fe3+ [Fe3+ ]e in this solution. Note: Your answer is assumed to be reduced to the highest power possible. Your Answer: x10 Answer units

the absorbance of an equilibrium mixture of Fescn2+ was measured at 447nm and found to be 0.319. What is the equilibrium concentration of FeSCN2+?

I have converted the NaCl (ppm) into NaCL (M) but am uncertain what the unquenched concentration fraction is and how to calculate it. Please see the attached image for the full question.