INSTRUMENTAL ANALYSIS EXAM
QUESTIONS AND DETAILED ANSWERS.
EXPERT VERIFIED FOR GUARANTEED
PASS.
Transducer - ANS A device that converts energy from one form to another-- electrical energy
to non electrical
processor - ANS processes signal
readout - ANS converts signals to something understandable by the human observer
External calibration - ANS Calibration procedure where a series of external standard samples
are prepared separately from the analytical sample; used when there are no interference
effects from matrix components in the analytical sample; calibration is accomplished by
measuring an analytical property, e.g. absorbance, as a function of analyte concentration in a
series of external standards; calibration curve is then used to predict concentration of
unknown.
standard addition - ANS A technique in which an analytical signal due to an unknown is first
measured. Then a known quantity of analyte is added, and the increase in signal is recorded.
From the response, it is possible to calculate what quantity of analyte was in the unknown.
spiking- adding known increments to sample aliquots containing identical volumes
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,internal standard - ANS A known quantity of a compound other than analyte added to a
solution containing an unknown quantity of analyte. The concentration of analyte is then
measured relative to that of the internal standard.
most accurate method
internal standard guidelines - ANS I.S. similar signal response with analyte
I.S. known to be absent from the sample
I.S. not affect signal intensity of the analyte
precision - ANS a measure of how close a series of measurements are to one another
-absolute std, relative srd. coefficient of variation, variance-
bias - ANS systematic error of an analytic method
absolute sys error, rel sys error
sensitivity - ANS ability to discriminate between small differences
calibration sensitivity, analytical sensitivity
detection limit - ANS minimum concentration or mass of analyte that can be detected at a
known confidence level
blank plus 3xSTD of the blank
dynamic range - ANS concentration LOQ to LOL
selectivity - ANS degree to which the method is free from interference by other species
contained in the sample matrix
coefficient of selectivity
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, LOD - ANS Limit of Detection- smallest amount detected
LOQ - ANS Limit of quantification- smallest amount quantifiable
LOL - ANS limit of linearity- limit that it is linear
Chemical Noise - ANS Random signal fluctuations that result from a variety of uncontrollable
variables, e.g. temperature, pressure, humidity, vibrations, etc.
Instrumental Noise - ANS Random signal fluctuations that are generated by particular
components of an analytical instrument, i.e. source, detector, electronics, etc.
Thermal Noise - ANS Is caused by random electron activity of the atoms that make up the
conductor, resistor, or any part of the passive circuit in question at any temperature above
absolute zero.
Flicker Noise - ANS 1/f, unknown causes
Shot Noise - ANS Caused by the random arrival of carriers at the output element of an
electronic device- electrons cross a junction
Environmental Noise - ANS anything in the environment that can affect the transmission or
reception of a signal
wavelength - ANS One crest to another
amplitude - ANS Max displacement from medium
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
QUESTIONS AND DETAILED ANSWERS.
EXPERT VERIFIED FOR GUARANTEED
PASS.
Transducer - ANS A device that converts energy from one form to another-- electrical energy
to non electrical
processor - ANS processes signal
readout - ANS converts signals to something understandable by the human observer
External calibration - ANS Calibration procedure where a series of external standard samples
are prepared separately from the analytical sample; used when there are no interference
effects from matrix components in the analytical sample; calibration is accomplished by
measuring an analytical property, e.g. absorbance, as a function of analyte concentration in a
series of external standards; calibration curve is then used to predict concentration of
unknown.
standard addition - ANS A technique in which an analytical signal due to an unknown is first
measured. Then a known quantity of analyte is added, and the increase in signal is recorded.
From the response, it is possible to calculate what quantity of analyte was in the unknown.
spiking- adding known increments to sample aliquots containing identical volumes
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,internal standard - ANS A known quantity of a compound other than analyte added to a
solution containing an unknown quantity of analyte. The concentration of analyte is then
measured relative to that of the internal standard.
most accurate method
internal standard guidelines - ANS I.S. similar signal response with analyte
I.S. known to be absent from the sample
I.S. not affect signal intensity of the analyte
precision - ANS a measure of how close a series of measurements are to one another
-absolute std, relative srd. coefficient of variation, variance-
bias - ANS systematic error of an analytic method
absolute sys error, rel sys error
sensitivity - ANS ability to discriminate between small differences
calibration sensitivity, analytical sensitivity
detection limit - ANS minimum concentration or mass of analyte that can be detected at a
known confidence level
blank plus 3xSTD of the blank
dynamic range - ANS concentration LOQ to LOL
selectivity - ANS degree to which the method is free from interference by other species
contained in the sample matrix
coefficient of selectivity
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, LOD - ANS Limit of Detection- smallest amount detected
LOQ - ANS Limit of quantification- smallest amount quantifiable
LOL - ANS limit of linearity- limit that it is linear
Chemical Noise - ANS Random signal fluctuations that result from a variety of uncontrollable
variables, e.g. temperature, pressure, humidity, vibrations, etc.
Instrumental Noise - ANS Random signal fluctuations that are generated by particular
components of an analytical instrument, i.e. source, detector, electronics, etc.
Thermal Noise - ANS Is caused by random electron activity of the atoms that make up the
conductor, resistor, or any part of the passive circuit in question at any temperature above
absolute zero.
Flicker Noise - ANS 1/f, unknown causes
Shot Noise - ANS Caused by the random arrival of carriers at the output element of an
electronic device- electrons cross a junction
Environmental Noise - ANS anything in the environment that can affect the transmission or
reception of a signal
wavelength - ANS One crest to another
amplitude - ANS Max displacement from medium
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
