Background: Paper chromatography is one method for testing the purity of compounds and identifying substances. Paper chromatography is a useful technique because it is relatively quick and requires small quantities of material.
Safety: Warnings: * Rubbing alcohol (or isopropyl alcohol) is flammable, so be sure to keep it away from high heat or heat sources. * Keep pigments and solutions away from your eyes, wash your hands carefully after coming in contact with any solutions or pigments, and clean up spills with soap and water immediately after they occur. * This lab can be a little messy, so be sure to work at a kitchen counter or in another area that can be easily wiped down if anything spills. It is also a good idea to lay down newspaper on the countertop before setting up the lab to help keep the counter surfaces clean.
Materials:
* Four different markers (including one black permanent marker) * Rubbing alcohol or isopropyl alcohol * Coffee filters (2) * Tall glasses or plastic cups (2) * Pencil * Ruler * Tape * Table salt * Water * Measuring cups/spoons * Clean pitcher or 2-liter bottle
Procedure:
1. Coffee filters usually are round, but it's easier to compare your results if the paper is rectangle. So, your first task is to cut the coffee filter into a rectangle measuring three cm by nine cm. You will need two of these strips to complete the lab. 2. Using a pencil (do not use a pen), draw a line one cm (1/2 inch) from the edge of one end of one strip of paper.
3. Make four pencil dots (one for each marker you will be examining) along this line, about 0.5 cm (1/4 inch) apart. Underneath each dot, label the marker that will be tested. You won't have space to write the whole color or brand name, so try abbreviations. 4. Use the markers to draw a different colored dot on each of the appropriate pencil marks on the paper strip. Allow the ink to dry, and