Paper Chromatography

• What is chromatography used for in chemistry?

  Separating substances in a mixture
• Paper chromatography is used to separate the different dyes in ink
• The baseline in paper chromatography is drawn using a pen

  False
• Steps in paper chromatography

  1️⃣ Draw a baseline on filter paper

  2️⃣ Add a sample of ink to the baseline

  3️⃣ Place the paper in solvent ensuring the baseline is not submerged

  4️⃣ Wait for the solvent to rise and separate the dyes

  5️⃣ Remove the paper and let it dry
• Why is it important to use a shallow amount of solvent in paper chromatography?

  To avoid submerging the baseline
• Placing a lid on the beaker in paper chromatography prevents the solvent from evaporating
• All chemicals in a sample will dissolve and move up the paper during chromatography

  False
• What is the pattern of spots left on the paper after chromatography called?

  Chromatogram
• The mobile phase in paper chromatography is always a liquid or a gas
• The stationary phase in paper chromatography is always a solid
• What determines how fast a chemical moves up the paper in chromatography?

  Its solubility in the solvent
• Chemicals that are more soluble in the solvent move faster in paper chromatography
• Match the phase with its description:

  Mobile phase ↔️ Substance molecules can move in

  Stationary phase ↔️ Substance molecules cannot move in
• The ratio used to compare the distance traveled by the substance to the distance traveled by the solvent is called the rf value
• If a substance travels 8 cm and the solvent travels 10 cm, the rf value is 0.8
• Why is it important to consider the solvent type when comparing rf values?

  It affects the移动 or stationary phase
• When a pure substance undergoes paper chromatography, it produces a single spot
• The rf value of a substance is constant regardless of the solvent used

  False