3.3.16.1 Principles of Chromatography

• Chromatography is a technique used to separate components of a mixture based on their different polarities
• Match the type of chromatography with its stationary phase:

  Paper Chromatography ↔️ Cellulose paper

  Thin Layer Chromatography ↔️ Silica gel or alumina

  Gas Chromatography ↔️ Solid or liquid-coated solid

  Column Chromatography ↔️ Solid adsorbent
• What type of compounds does the mobile phase carry strongly in chromatography?

  Polar compounds
• What are the two phases involved in chromatography?

  Mobile and stationary
• Chromatography is a separation
• Chromatography allows for the identification and quantification of mixture components.


  True
• Components with higher affinity for the mobile phase elute faster in chromatography.


  True
• Higher polarity of a component decreases its retention time in chromatography.

  False
• Match the chromatography technique with its application:

  GC ↔️ Analyze volatile compounds in air

  HPLC ↔️ Quantify active ingredients in drugs

  TLC ↔️ Screen for compounds in plant extracts

  Column Chromatography ↔️ Purify a protein from cell lysate
• Highly polar compounds in chromatography move faster through the stationary phase.

  False
• Less polar components spend more time in the mobile
• Match the phase with its polarity interaction:

  Stationary Phase ↔️ Stronger retention of polar compounds

  Mobile Phase ↔️ Stronger affinity for non-polar compounds
• What is the composition of the mobile phase in chromatography?

  Liquid or gas
• What role does polarity play in the separation process in chromatography?

  Differential interactions
• What is retention time in chromatography?

  Time a component spends in the system
• What is one factor that influences separation efficiency in chromatography?

  Flow rate of mobile phase
• The mobile phase in chromatography can only be a liquid.

  False
• The mobile phase in chromatography carries the mixture through the system
• The stationary phase retains polar compounds longer than non-polar compounds.


  True
• The mobile phase can only be liquid in chromatography.

  False
• Steps in the separation process in chromatography:

  1️⃣ Mixture components are carried by the mobile phase

  2️⃣ Components interact with the stationary phase based on polarity

  3️⃣ Components with higher affinity for the stationary phase move slower

  4️⃣ Differential affinities cause separation
• Paper chromatography uses capillary action through paper
• The stationary phase is a fixed solid or liquid-coated solid that interacts with components based on their polarity
• Greater affinity for the stationary phase prolongs retention