Paper Chromatography

What is the main purpose of paper chromatography?

To separate and identity mixtures

What type of paper is used in paper chromatography?

Filter Paper

In paper chromatography, the stationary phase is:

The paper

What serves as the mobile phase in paper chromatography?

The solvent

The movement of substances in paper chromatography depends on:

Their solubility in the mobile phase

The separation of components in paper chromatography is due to differences in:

Solubility and Absorption

The Rf value in paper chromatography is calculated by:

Dividing the distance traveled by the sample by the distance traveled by the solvent

Why should the solvent line be marked with a pencil?

To ensure it doesn't dissolve in the solvent

In paper chromatography, why should the sample spot be small?

To ensure sharp and clear separation of components

If two components have the same Rf value, they are likely:

The same substance

Which of the following factors does not affect the separation in paper chromatography?

Length of the paper

What should be avoided when setting up a paper chromatography experiment?

• Using a mixture sample

• Allowing the solvent front to touch the edges of the paper

Why is the chromatographic paper suspended in a closed container?

To prevent evaporation of the solvent

The separation of pigments in plant leaves can best be studied using:

Paper Chromatography

The point where the solvent stops on the chromatogram is called:

The solvent front

Why is it important to place the chromatographic paper above the solvent level initially?

To avoid washing off the sample

Which type of mixtures is paper chromatography best suited for?

Complex mixtures of liquids

The pigments that travel farther up the paper are generally:

More soluble in the mobile phase

The pattern of separated substances on the paper.

Chromatogram

The principle of paper chromatography is based on

Distribution of compounds between the mobile and stationary phases

What is the primary purpose of paper chromatography?

To separate mixtures of liquids

In paper chromatography, the stationary phase is:

The paper

What does the mobile phase refer to in paper chromatography?

The solvent

Which of the following is NOT a common solvent used in paper chromatography?

Air

In paper chromatography, what property of substances causes them to separate?

Solubility

The distance traveled by the solvent front in paper chromatography is called:

The solvent front

What influences the rate of movement of substances in paper chromatography?

Solubility and adsorption

Which term describes the ratio of the distance a component moves to the distance the solvent front moves?

Rf Value

What happens to the components of a mixture in paper chromatography?

They separate based on solubility and adsorption

If two components have the same Rf value, what does it suggest?

They are chemically identical

How is the mobile phase typically applied in paper chromatography?

By placing the paper in a solvent

What would happen if the solvent front exceeds the top of the paper?

The chromatography will fail

Why is it important not to let the solvent touch the ink spot directly?

It will cause the spot to spread uncontrollably

What does the appearance of multiple spots on the paper indicate?

The sample contains multiple components

In paper chromatography, which is true about non-polar substances?

They travel faster than polar substances

What is the main difference between paper chromatography and thin-layer chromatography?

The type of stationary phase used

Which of the following is most appropriate for separating food colorings in paper chromatography?

Using water as the solvent

What is the typical result of paper chromatography when separating a complex mixture?

A series of separate spots

What would be a reason for no separation in paper chromatography?

The sample was not spotted correctly

What is one disadvantage of paper chromatography?

It cannot separate mixtures effectively with low solubility differences

What does the Rf value represent in paper chromatography?

The ratio of the distance traveled by a substance to the solvent front

How is the Rf value calculated?

Distance traveled by the substance ÷ Distance traveled by the solvent front

What is the typical range of Rf values?

0 to 1

What does an Rf value of 0 indicate?

The substance did not move

What does an Rf value of 1 indicate?

The substance traveled the same distance as the solvent front

Which of the following affects the Rf value?

The type of solvent used

If two substances have the same Rf value under the same conditions, what can be inferred?

They are likely the same substance

What happens to the Rf value if a more polar solvent is used?

It increases for polar substances

Why is it important to keep the Rf value consistent?

To compare substances across experiments

Which factor does NOT influence the Rf value?

The color of the substance

If a substance travels 2 cm and the solvent front travels 8 cm, what is the Rf value?

0.25

An Rf value can help identify a substance by comparing it to:

Known Rf values in a reference database

Why might the Rf value differ between experiments?

Different solvents or conditions are used

What does a low Rf value suggest about a substance?

It interacts strongly with the stationary phase

How can Rf values improve the accuracy of chromatography results?

By providing a quantitative comparison

If the Rf value of a substance is 0.5, what does it mean?

It moved half the distance of the solvent front

Which combination will give the highest Rf value?

A non-polar substance and a non-polar solvent

In paper chromatography, substances with higher Rf values are typically:

More soluble in the solvent

What would happen to the Rf value if a solvent evaporates during the experiment?

The Rf value would decrease or become inaccurate

If two substances have Rf values of 0.3 and 0.7, what does this indicate?

They interact differently with the stationary and mobile phases