General Chemistry 1025c Mixtures Vs Pure Substances Using Chromatography For Separation Lab-Sl printable pdf download

General Chemistry 1025c Mixtures Vs Pure Substances Using Chromatography For Separation Lab-Sl

Student Name_________________________________

Lab Partner’s Name_____________________________

Date_________________________________________

General Chemistry 1025C

Mixtures Vs Pure Substances

Using Chromatography for Separation Lab-SL

Objective: In this lab, you will be determining if substances contain just one element or compound (pure

substances) or a mixture of several substances. Chromatography will be the tool used to make your

determination. In this lab, each student will perform his/her own chromatographic separation.

Chromatography is basically the study of separations of mixtures. It is frequently used to identify unknown

components in a mixture. Paper chromatography uses paper as a stationary surface. Small spots of mixtures

are placed on the paper. The edge of the paper is then placed in a liquid solvent. As the liquid moves up the

paper by capillary action, it carries any components in the “spot of mixture” with it. The components;

however, move at differing rates depending on their solubility in the liquid. Thus the “spot of mixture” is

separated into its component parts as it is carried up the chromatographic paper by the liquid.

In this lab, you will be determining whether the color used in different markers is composed of a pure

substance or a mixture of substances by examining the chromatographic separations.

Materials:

Chromatography Paper, cut into 7 cm x 12 cm

Ruler

600 ml beaker

Straw

Colored pens (washable)

Procedure:

1. Obtain a piece of chromatography paper. Using a pencil, draw a line 2 cm from the bottom edge and make

6 small marks at 1 cm intervals along the line.

General Chemistry 1025c Mixtures Vs Pure Substances Using Chromatography For Separation Lab-Sl