Title of Lab: The Melting Temperature of a Pure Substance
Purpose: The goal of this experiment was to find the melting point of Paradichlorobenzene and to observe the freezing/melting of a substance. The purpose was to also observe an endothermic and exothermic process. Introduction: The uses of Paradichlorobenzene are mainly as a fumigant for the control of moths, molds, and mildews, and as a space deodorant for toilets and refuse containers. It is also used as an intermediate in the production of other chemicals, in the control of tree-boring insects and in the control of mold in tobacco seeds. The melting point of Paradichlorobenzene is about 53 degrees Celsius (127 Fahrenheit). A melting/freezing point is the equilibrium of a solid to a liquid or a liquid to a solid. Materials: The materials used during this experiment are two beakers, three-fourths of tap water in each, a hotplate, a test tube containing Paradichlorobenzene, two thermometers, a timer, a clamp, and a ring stand. Methods/Procedure: The procedure used for this experiment was detailed on the handout entitled ‘’Melting Temperature of a Pure Substance’’. No changes were made. Part 1
First prepare a hot water bath, fill a beaker with about three-fourths of tap water, and place it on the hot plate on medium heat. Fill the test-tube with Paradichlorobenzene and place it in the hot water until it completely melts. Place a thermometer in the Paradichlorobenzene and continue heating until the temperature reaches anywhere between 65 to 70 degrees Celsius. Next fill the other beaker with three-fourths of tap water and place it on the base of the ring stand. Then using your clamp, clamp the test tube containing the melted Paradichlorobenzene and position it over the beaker filled with water. Now with the help of a partner record the temperatures and any observations after every thirty seconds. Record the temperature of the Paradichlorobenzene to the nearest 0.2...