Week 3 Topic 1.4

The physical separation of mixtures into individual components is..

• chromatography
• opacity 
• latent
• trace evidence 

The diagram below shows a chromatogram obtained when a sample X was analysed together with four other known dyes P, Q, R and S. Dye Q was known to cause cancer. Which of the following dye(s) is/are safe for use?

• P only
• S only
• P and S
• P and X

The R_f value  for the blue component is 

• 0.3
• 0.7
• 10
• 3

The R_f value  for the red component is 

• 0.3
• 0.7
• 10
• 7

The substance in the mixture that has the greatest affinity for the stationary phase will travel

• fastest
• slowest

The mobile phase in TLC is typically a

• plasma
• solid
• gas
• liquid

The substance in the mixture that has the greatest affinity for the mobile phase will travel

• fastest
• slowest

In the image, which dye has the largest retention factor (R_f)?

• Red

• Blue

• Purple

In the image, which dye has the smallest retention factor (R_f)?

• Red

• Blue

• Purple

Which plant species has plant pigments most similar to those in A?

• B
• C
• D