INSTRUMENTAL ANALYSIS ACS EXAM
STUDY GUIDE 2026 COMPREHENSIVE
QUESTIONS AND SOLUTIONS
◉ photomultiplier tube
Answer: -An apparatus that converts a photon of visible light into an
electrical pulse
-most sensitive photodetector
◉ CCD
Answer: -is a silicon-based multichannel array detector of UV, visible
and near-infra light
-sensitive to light
◉ Beer's Law extension to mixtures of compounds
Answer: -can extend to sample containing several absorbing
components if there are no interactions
-individual absorbances are additive
-low concentration analytes
-assumes one monochromatic wavelength
-
, ◉ Sensitivity of absorbance methods
Answer: -low sensitivity at low sample concentrations
◉ Sensitivity of Fluorescence methods
Answer: -sensitivity is x1000 greater than absorption
-leads to more accurate and precise results
-more expensive because of this
◉ Ion Selective Electrodes (ISE)
Answer: -transducer that converts the activity of a specific ion
dissolved in a solution into an electrical potential.
◉ Electrochemical detector (HPLC)
Answer: -analyte gets either oxidized or reduced at the working
electrode
-only responds to compound that can partake in redox reactions
-measures current when an electroactive solute emerges from the
column and passes over the working electrode.
◉ Potentiometry
Answer: the use of electrodes to measure voltages that provide
chemical information
STUDY GUIDE 2026 COMPREHENSIVE
QUESTIONS AND SOLUTIONS
◉ photomultiplier tube
Answer: -An apparatus that converts a photon of visible light into an
electrical pulse
-most sensitive photodetector
◉ CCD
Answer: -is a silicon-based multichannel array detector of UV, visible
and near-infra light
-sensitive to light
◉ Beer's Law extension to mixtures of compounds
Answer: -can extend to sample containing several absorbing
components if there are no interactions
-individual absorbances are additive
-low concentration analytes
-assumes one monochromatic wavelength
-
, ◉ Sensitivity of absorbance methods
Answer: -low sensitivity at low sample concentrations
◉ Sensitivity of Fluorescence methods
Answer: -sensitivity is x1000 greater than absorption
-leads to more accurate and precise results
-more expensive because of this
◉ Ion Selective Electrodes (ISE)
Answer: -transducer that converts the activity of a specific ion
dissolved in a solution into an electrical potential.
◉ Electrochemical detector (HPLC)
Answer: -analyte gets either oxidized or reduced at the working
electrode
-only responds to compound that can partake in redox reactions
-measures current when an electroactive solute emerges from the
column and passes over the working electrode.
◉ Potentiometry
Answer: the use of electrodes to measure voltages that provide
chemical information
