INSTRUMENTAL ANALYSIS ACS EXAM 2026- WELL REVISED ASSESSMENT EXAM WITH VERIFIED ANSWERS

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INSTRUMENTAL ANALYSIS ACS EXAM
2026- WELL REVISED ASSESSMENT EXAM
WITH VERIFIED ANSWERS


How to calculate signal to noise - correct-answer -S/N = mean/STDEV


-inverse of RSD
-STDEV: 5 (#STDEV gaussian curve)
-STDEV: peak-to-peak noise/5




S/N relationships - correct-answer --increase S/N, increase run time
-decrease noise, increase S/N




Beer's Law - correct-answer -




Beer's Law Calculations - correct-answer -

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Hard ionization vs soft ionization - correct-answer --hard: no M+ peak (or small)
-soft: M+ peak is visible




MS: hard ionization sources - correct-answer --impart high quantities of residual
energy in the subject molecule invoking large degrees of fragmentation




MS: hard ionization sources examples - correct-answer --electron impact




Electron Impact (EI) - correct-answer --Uses electron impact to ionize a molecule
-gas phase
-energetic electrons
-possibility of over fragmentation
-hard
-most common




EI advantages - correct-answer --good stability
-universal ionization
-reproducible spectra