1 Separation and Purification Quiz 3

A chromatogram of an unknown ink was developed along with common dyes. Which dyes are present in the ink?

• 1 & 2

• 1 & 4

• 2 & 3

• 2 & 4

A paper chromatogram of a pure compound was developed.

    Which statement about the chromatogram is true?

• The compound will be separated into the individual elements. 

• The R_f value(s) of the spot(s) observed are larger than 0.5.

• A locating agent must be used to interpret the chromatogram.

• There will be only be one spot on the chromatogram.

A student found an unlabelled bottle of white powder. He suspects that the powder is aspirin, a medicine used as a painkiller. He used chromatography to test his hypothesis. The diagram shows his chromatogram.

Calculate the R_f values of the unknown powder.

A student found an unlabelled bottle of white powder. He suspects that the powder is aspirin, a medicine used as a painkiller. He used chromatography to test his hypothesis. The diagram shows his chromatogram.

Calculate the R_f values of aspirin.

Is the unknown powder aspirin? Explain using the R_f values calculated in previous two questions.