Free Analytical Chemistry MCQs with Answers
105 Analytical Chemistry MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Analytical chemistry identifies and measures substances using separation and instrumental methods. Chromatography is studied through stationary and mobile phases, retention and Rf values, while spectroscopy connects absorption of electromagnetic radiation with molecular structure and supports qualitative and quantitative analysis through techniques such as UV-visible and infrared spectroscopy.
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Read the Analytical Chemistry notesFree MDCAT chapter notes with key terms105 questions · page 2 of 6
- A. Dialysis
- B. Chromatography
- C. HPLC
- D. FPLC
Explanation: Dialysis is a separation process that uses a semipermeable membrane to separate small solute molecules from larger molecules (like…
Correct answer: Dialysis- A. Acid-base titration
- B. Redox titration
- C. Precipitation titration
- D. All above methods
Explanation: All forms of titration are chemical methods of analysis because they rely on a specific chemical reaction (neutralization…
Correct answer: All above methods- A. Optical method
- B. Colorimetry
- C. Polarography
- D. Gravimetric analysis
Explanation: Gravimetric analysis is a classical or "wet chemical" method that relies on the measurement of mass, typically by weighing a precipitate.
Correct answer: Gravimetric analysis- A. Separation of sample in pure form
- B. Separation of the sample in the mixture form
- C. Preparation of sample for the analysis
- D. Validity of experimental results
Explanation: A key step in most chemical analyses is to separate the analyte of interest from interfering substances in the mixture.
Correct answer: Separation of the sample in the mixture form- A. 1 - 10 mg or < 50 µL
- B. 10 - 20 mg or > 50 µL
- C. 50 - 100 mg or < 100 µL
- D. 100 - 1000 mg or > 1000 µL
Explanation: Analytical methods are often classified by the size of the sample used.
Correct answer: 1 - 10 mg or < 50 µL- A. 10 - 1000 mg
- B. 10 - 100 mg
- C. 1 - 10 mg
- D. 20 - 1000 mg
Explanation: Semi-micro analysis is the category of chemical analysis that deals with sample sizes that are smaller than macro analysis but larger than…
Correct answer: 10 - 100 mg- A. 1% or more
- B. 0.1%
- C. 0.01%
- D. 0.001%
Explanation: In compositional analysis, components are classified by their relative abundance.
Correct answer: 1% or more- A. 0.1 to 1%
- B. 0.01 to 1%
- C. 1 to 10%
- D. None of above
Explanation: A minor constituent is a component that is present in a smaller amount than a major constituent but is still significant.
Correct answer: 0.01 to 1%- A. < 10%
- B. < 20%
- C. < 1.0%
- D. < 0.01%
Explanation: A trace constituent is a component that is present in a very small or minute amount.
Correct answer: < 0.01%- A. Sampling
- B. Conversion of the desired constituent into a suitable form for analysis
- C. Measurement of some physical or chemical property, on which the determination is based
- D. All above steps
Explanation: A complete quantitative analysis involves multiple steps. These include obtaining a representative sample, preparing the sample for…
Correct answer: All above steps- A. Mean value
- B. Low value
- C. True value
- D. None of above
Explanation: Accuracy is a measure of how close an experimental measurement is to the true or accepted value of the quantity being measured.
Correct answer: True value- A. N14
- B. P31
- C. Cl35
- D. C13
Explanation: NMR spectroscopy requires nuclei with non-zero spin to be detected. Cl³⁵ has a quadrupolar nucleus with spin 3/2 and often gives broad…
Correct answer: N14- A. Fe4[Fe(CN6)]3
- B. Na3[Fe(CN)6]
- C. K3[Fe(CN)6]
- D. None
Explanation: In the Lassaigne's test, nitrogen in an organic compound forms sodium cyanide (NaCN) when fused with Na.
Correct answer: Fe4[Fe(CN6)]3- A. -SO3H
- B. -OH
- C. -NH2
- D. Both -SO3H and -NH2
Explanation: Auxochromes are groups that enhance color by altering the electron distribution in a chromophore.
Correct answer: -SO3H- A. Aston spectrometer
- B. Dempster's mass spectrometer
- C. Soddy mass spectrometer
- D. Atomic spectrometer
Explanation: The Aston mass spectrometer was designed to separate and identify isotopes based on their mass-to-charge ratio.
Correct answer: Aston spectrometer- A. Surrounding
- B. System
- C. Confined space
- D. None of these
Explanation: In laboratory terminology, a system is the part of the universe under study or observation.
Correct answer: System- A. Change the pH drastically
- B. Resist changes in pH
- C. Act as a strong acid
- D. Act as a strong base
- E. Add color to the solution
Explanation: A buffer contains a weak acid and its conjugate base (or vice versa). It neutralizes added acids or bases, maintaining nearly constant pH.
Correct answer: Resist changes in pH- A. Its original compound
- B. A volatile compound
- C. An insoluble precipitate
- D. A dissolved solution
Explanation: Gravimetric analysis involves precipitating the analyte in a stable, pure form.
Correct answer: An insoluble precipitate- A. The standard deviation
- B. The average deviation
- C. Relative mean deviation
- D. Variance
Explanation: This is the definition of average deviation. It is calculated by finding the absolute difference of each measurement from the mean…
Correct answer: The average deviation- A. C.V.= (8 X 100) / X
- B. C.V.=(x X 100) / 8
- C. C.V.= (x X 8) / 100
- D. C.V.= (8 X 1000) / X
Explanation: The coefficient of variation is a standardized measure of the dispersion of a data set.
Correct answer: C.V.= (8 X 100) / X