Vernier Software and Technology
Vernier Software & Technology

Liquid Chromatography

Introduction

Chromatography is a process used to separate the components of a mixture. A mixture is injected into a chromatography column, where it lands on a substrate, also known as the stationary phase. The stationary phase may be polar, attracting polar substances, or nonpolar, attracting nonpolar substances. When a mixture is injected into a chromatography column, the substances in the mixture cling to the stationary phase. Next, a solvent is injected into the column. The solvent is called the mobile phase. As the solvent moves along the stationary phase, it will carry the components with it. When and how quickly the substances are carried out of the column by the solvent depends on the polarity of the substances and their solubility in the solvent. If the solubilities and/or polarities of the individual parts of the mixture are significantly different, the substances in the mixture will separate from each other as the mixture travels along the substrate. The substance that is the most strongly attracted to the solvent will be the first to leave the chromatography column. The substrate (stationary phase) and the solvent (mobile phase) can be in any phase, depending on the properties and concentrations of the components in a given mixture. Therefore, there is solid, liquid, and gas chromatography.

In this experiment, you will use liquid chromatography to separate the dyes, FD&C Blue and FD&C Red that are found in grape-flavored Kool-Aid®, from the other ingredients in the dry drink product. You will use a special column, called a C18 Sep-Pac® for the experiment. This column contains a silica solid with a C18 hydrocarbon bonded to it, which renders the solid nonpolar.

Objectives

In this experiment, you will

  • Conduct an isocratic, liquid-chromatographic separation.
  • Conduct a step gradient, liquid-chromatographic separation.
  • Complete the necessary measurements and calculations to evaluate the components of a mixture that have been separated by liquid chromatography.

Sensors and Equipment

No probeware required for this experiment.

Standards Correlations

See all standards correlations for Advanced Chemistry with Vernier »

Advanced Chemistry with Vernier

See other experiments from the lab book.

1The Determination of a Chemical Formula
2The Determination of the Percent Water in a Compound
3The Molar Mass of a Volatile Liquid
4Using Freezing-Point Depression to Find Molecular Weight
5The Molar Volume of a Gas
6Standardizing a Solution of Sodium Hydroxide
7Acid-Base Titration
8An Oxidation-Reduction Titration: The Reaction of Fe2+ and Ce4+
9Determining the Mole Ratios in a Chemical Reaction
10The Determination of an Equilibrium Constant
11Investigating Indicators
12The Decomposition of Hydrogen Peroxide
13Determining the Enthalpy of a Chemical Reaction
14ASeparation and Qualitative Analysis of Cations
14BSeparation and Qualitative Analysis of Anions
15AThe Synthesis of Alum
15BThe Analysis of Alum
16Conductimetric Titration and Gravimetric Determination of a Precipitate
17Determining the Concentration of a Solution: Beer's Law
18Liquid Chromatography
19Buffers
20Electrochemistry: Voltaic Cells
21Electroplating
22The Synthesis and Analysis of Aspirin
23Determining the Ksp of Calcium Hydroxide
24Determining Ka by the Half-Titration of a Weak Acid
25The Rate and Order of a Chemical Reaction
26The Enthalpy of Neutralization of Phosphoric Acid
27α, β, and γ
28Radiation Shielding
29The Base Hydrolysis of Ethyl Acetate
30Exploring the Properties of Gases
31Determining Avogadro's Number
32Potentiometric Titration of Hydrogen Peroxide
33Determining the Half-Life of an Isotope
34Vapor Pressure and Heat of Vaporization
35Rate Determination and Activation Energy

Experiment 18 from Advanced Chemistry with Vernier Lab Book

<i>Advanced Chemistry with Vernier</i> book cover

Included in the Lab Book

Vernier lab books include word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.

Buy the Book

Go to top