Chromatography Quiz

What is the basis of analysis in chromatography?

• A method of chemical synthesis

• A method of separation

• A type of chemical reaction

• A method of protein synthesis

Answer explanation

Chromatography is primarily a method of separation that allows for the isolation of different components in a mixture based on their movement through a stationary phase. Thus, the correct answer is 'A method of separation'.

Which of the following is a type of planar chromatography?

• Ion Exchange Chromatography

• Thin Layer Chromatography

• High Performance Liquid Chromatography

• Gas Chromatography

Answer explanation

Thin Layer Chromatography (TLC) is a type of planar chromatography where the stationary phase is a thin layer of adsorbent on a flat surface. The other options are not classified as planar chromatography.

In size exclusion chromatography, which type of molecules elute first?

• All molecules elute simultaneously

• Large aggregates

• Medium-sized molecules

• Small molecules

Answer explanation

In size exclusion chromatography, larger molecules, such as large aggregates, elute first because they cannot enter the pores of the stationary phase, allowing them to pass through the column more quickly than smaller molecules.

What is the primary principle behind ion exchange chromatography?

• Separation based on solubility

• Separation based on molecular weight

• Separation based on charge

• Separation based on size

Answer explanation

Ion exchange chromatography separates molecules based on their charge. Charged particles interact with oppositely charged resin, allowing for selective retention and elution, making 'separation based on charge' the correct principle.

What does the Rf value in planar chromatography represent?

• The temperature of the chromatography process

• The concentration of the sample

• The retention factor of a compound

• The rate of flow of the mobile phase

Answer explanation

The Rf value, or retention factor, in planar chromatography indicates the relative distance traveled by a compound compared to the solvent front. It is a key parameter for identifying compounds in the mixture.

Which chromatography technique is best suited for separating proteins based on their interactions with ligands?

• Adsorption Chromatography

• Affinity Chromatography

• Ion Exchange Chromatography

• Size Exclusion Chromatography

Answer explanation

Affinity Chromatography is specifically designed to separate proteins based on their specific interactions with a ligand, making it the best choice for affinity-based separation compared to other techniques.

In High Performance Liquid Chromatography (HPLC), what is the purpose of gradient elution?

• To increase the viscosity of the mobile phase

• To reduce analysis time

• To achieve sharper peaks and better separation

• To maintain a constant solvent composition

Answer explanation

Gradient elution in HPLC allows for a gradual change in solvent composition, which enhances the separation of compounds. This results in sharper peaks and improved resolution, making it easier to distinguish between closely eluting substances.

What is the primary advantage of using High Performance Liquid Chromatography (HPLC) over traditional liquid chromatography?

• Ability to analyze only solid samples

• Longer column life

• Lower cost of operation

• Higher resolution and sensitivity

Answer explanation

The primary advantage of HPLC over traditional liquid chromatography is its higher resolution and sensitivity, allowing for better separation and detection of compounds in complex mixtures.

Which type of chromatography is primarily used for the separation of volatile compounds?

• Thin Layer Chromatography

• Gas Chromatography

• Liquid Chromatography

• High Performance Liquid Chromatography

What is the role of the detector in chromatography?

• To prepare the sample for analysis

• To maintain the temperature of the column

• To identify and quantify the separated compounds

• To mix the mobile phase