MLS Chemistry Exam| 437 QUESTIONS| WITH COMPLETE SOLUTIONS

Which of the following lamps provides a continuous spectrum of radiant energy in the visible, near IR and near UV regions of the spectrum? Correct Answer: Tungsten filament Which of the following isolates light within a narrow region of the spectrum? Correct Answer: Monochromator Which of the following is not descriptive of a photomultiplier tube? Correct Answer: Cannot be used with a chopper Which of the following is false about a photomultiplier tube? Correct Answer: Is composed of an iron plate and a layer of selenium Which type of photodetector employs a linear arrangement that allows it to respond to a specific wavelength resulting in complete UV visible spectrum analysis? Correct Answer: Photodiode array When performing spectrophotometer quality assurance checks, what is the holmium oxide glass filter used to assess? Correct Answer: Wavelength accuracy In spectrophotometric analysis, what is the purpose of the reagent blank? Correct Answer: Correct for color contribution of the reagents In regard to bichromatic analysis, which of the following is false? Correct Answer: Absorbance is measured at the spectral absorbance peak for a blank and the sample using the same wavelength The bandpass of a spectrophotometer is 10 nm. If an instrument is set at 540 nm, the wavelengths that are permitted to impinge on the sample will be within what wavelength range? Correct Answer: 535 to 545 nm Which of the following formulas is an expression of the Beer Lambert law that is routinely applied to spectrophotometric analysis? Correct Answer: Au X Cs / As = Cu In spectrophotometry, which of the following is a mathematical expression of the relationship between absorbance and transmittance? Correct Answer: A = 2 - log % T Which of the following is not a problem inherent in turbidimetry? Correct Answer: Need to maintain a constant and specific temperature Which of the following may be associated with reflectance spectrophotometry as it relates to the dry reagent slide technique? Correct Answer: Unabsorbed, reflected light detected by photodetector