GC Quiz 1

What is the primary function of the carrier gas in gas chromatography (GC)?

• To detect the sample

• To separate the sample

• To carry the sample through the GC system

• To vaporize the sample

Which of the following gases is commonly used as a carrier gas in GC?

• Oxygen

• Helium

• Carbon dioxide

• Methane

What purity level is recommended for carrier gases in GC?

• 95%

• 98%

• 99.995%

• 100%

What does a split injection method in GC do?

• Introduces all the sample onto the column

• Removes contaminants from the sample

• Divides the sample into two unequal portions

• Reduces column temperature

Which column type offers the highest resolution in GC?

• Packed column

• Capillary column

• Split column

• Thin-film column

Which stationary phase interaction is most relevant for non-polar analytes?

• Hydrogen bonding

• Dipole-dipole interactions

• Dispersion forces

• Ionic bonding

What determines the optimum column temperature in GC?

• Column length

• Boiling point of the sample

• Detector type

• Carrier gas pressure

Which stationary phase is best for highly polar compounds?

• DB-5

• DB-5

• DB-WAX

• DB-1

What is the ideal split ratio range in GC split injection?

• 1:1 - 5:1

• 10:1 - 100:1

• 200:1 - 500:1

• 500:1 - 1000:1