The purpose of this laboratory was to determine how different substances have different solubilities in a given solvent. This was accomplished using the method of chromatography. The solubility of each substance was first determined by dropping a drop or two of each on a line drawn 2 inches above the bottom of a piece of paper. Then the paper was lightly bent in order to tape both sides of the paper leaving about a 4 centimeter gap so that the sides of the paper are not touching.
The paper was then put into a beaker of a hydrochloric acid, ethanol, and butanol mixture, being sure that the paper does not touch the sides of the beaker, and then topped. After the eluting solution has risen to within two centimeters of the top of the filter paper, the paper was removed from the beaker, dried, and was stained with a staining reagent solution containing potassium ferrocyanide and potassium iodide. This reagent forms colored precipitates or reaction products with many cations, including all of those used in this experiment. The distance of which the spots moved were determined by calculating the Rf value of each substance.
The Rf value is determined by following formula: This experiment was successful overall, given a few errors. This experiment was done twice due to the paper having pen ink marks which interfered with the movement of the substances in the first experiment. During the second trial, it was a little difficult to measure the distance the substances traveled because multiple drops of each were dropped right above each other rather than on top of each other. By the end of the experiment, the distance traveled by each substance and the color changes of each substance was still clear and was able to be measured and recorded.
The Essay on Free Fall Experiment
Abstract In this experiment we studied the motion of an object in free fall, that is an object being dropped from a certain height to Earth’s surface. In this experiment we tested the idea that no matter what the size, shape, color, etc. of the object if it would still experience the same constant acceleration throughout its fall (short distance). The constant downward acceleration it experiences ...
