Q. In electrophoresis, what factor primarily influences the migration speed of ions?
A.Ion concentration
B.Electric field strength
C.Temperature of the buffer
D.Size of the gel pores
Solution
The migration speed of ions in electrophoresis is primarily influenced by the strength of the electric field applied.
Correct Answer: B — Electric field strength
Q. In infrared spectroscopy, which functional group would show a strong absorption around 1700 cm-1?
A.Alcohols
B.Aldehydes
C.Carboxylic acids
D.Ketones
Solution
Ketones typically show a strong absorption around 1700 cm-1 due to the C=O stretching vibration.
Correct Answer: D — Ketones
Q. In mass spectrometry, what does the term 'm/z' represent?
A.Mass to charge ratio
B.Molecular weight
C.Ionization energy
D.Retention time
Solution
The term 'm/z' represents the mass to charge ratio of ions detected in mass spectrometry.
Correct Answer: A — Mass to charge ratio
Q. What is the main advantage of using UV-Vis spectroscopy for qualitative analysis?
A.It can detect all types of ions
B.It provides structural information
C.It is non-destructive
D.It is highly sensitive to color changes
Solution
UV-Vis spectroscopy is non-destructive, allowing for the analysis of samples without altering their composition.
Correct Answer: C — It is non-destructive
Q. What is the primary principle behind the use of thin-layer chromatography (TLC) for qualitative analysis?
A.Separation based on boiling point
B.Separation based on solubility
C.Separation based on size
D.Separation based on charge
Solution
TLC separates compounds based on their solubility in the mobile phase and their interaction with the stationary phase.
Correct Answer: B — Separation based on solubility
Q. What is the primary purpose of using ion chromatography in qualitative analysis?
A.To separate ions based on their charge
B.To identify the presence of specific ions in a mixture
C.To measure the concentration of ions
D.To determine the molecular weight of ions
Solution
Ion chromatography is primarily used to identify the presence of specific ions in a mixture by separating them based on their interactions with the stationary phase.
Correct Answer: B — To identify the presence of specific ions in a mixture
Q. What is the role of a buffer in a titration involving a weak acid and a strong base?
A.To increase the reaction rate
B.To maintain a constant pH
C.To enhance the solubility of the acid
D.To provide a color change indicator
Solution
A buffer helps maintain a constant pH during the titration, which is crucial for accurate endpoint determination.
Correct Answer: B — To maintain a constant pH
Q. Which of the following ions can be detected using flame photometry?
A.Sodium
B.Calcium
C.Potassium
D.All of the above
Solution
Flame photometry can detect multiple alkali and alkaline earth metal ions, including sodium, calcium, and potassium.
Correct Answer: D — All of the above
Q. Which qualitative analysis technique is most effective for detecting trace metals in a sample?
A.Atomic absorption spectroscopy
B.Nuclear magnetic resonance
C.Infrared spectroscopy
D.Gas chromatography
Solution
Atomic absorption spectroscopy is highly effective for detecting trace metals due to its sensitivity and specificity.
Correct Answer: A — Atomic absorption spectroscopy
Q. Which technique is best suited for the separation of charged biomolecules based on their size?
A.Gas chromatography
B.Capillary electrophoresis
C.High-performance liquid chromatography
D.Thin-layer chromatography
Solution
Capillary electrophoresis is best suited for separating charged biomolecules based on their size and charge.
