Classification Of Solid Substances

545 Words3 Pages
Title: Classification of Solid Substances Objective: To The purpose of this lab is to classify several unknown substances into one the five categories. There Materials Used: Power supply, circuit board, Bunsen Burner, test tubes, 100mL beaker, a piece of Tin(Sn), test tube clamp, sodium chloride (NaCl), sucrose, candle wax, sand (silica), striker, four unknown compounds, acetone, deionized water. Procedure: Perform the following test and use the results to classify the unknown substances: 1. Solubility Test: The two solvents are water and hexane. Water is a polar solvent and acetone is a nonpolar solvent. If the substance dissolves in one solvent, it should not dissolve in the other. a. Place a half-pea-size amount in a small test tube and add enough water to fill the test tube with 2 to 3 cm of solvent. Stir gently with a stirring rod for at least 20 seconds. b. If it doesn’t dissolve in water, pour off the water from the test tube and add the acetone. Stir gently for 20 seconds. 2. Melting Point Test a. Put a small pea-size amount of solid in the bottom of a test tube. Hold the test tube with a test tube holder and move it back and forth through the flame. If the substance melts after 10-15 seconds, it has a low melting point. b. If the substance has not melted, hold it directly over the flame. If the substance now melts, it has a medium melting point. c. If the substance does not melt after several minutes of direct heating, it has a high melting point. 3. Solution Conductivity Substances will only conduct if there are free moving ions present in the solution. The mobile ion allows a current to flow and completes the circuit. Data and Calculations: Known Tests/ Observations Classifications I High Melting Point/Dissolved in H2O not in acetone. Ionic: ¬-KNO3, KCl, NaCl II Dissolved in H2O not in acetone. Non Polar
Open Document