Honors Chemistry Experiment : Lab Techniques Purpose: The purpose of this experiment is to observe a chemical reaction and separate the products by filtration. The reactants are aqueous solutions of Lead II Nitrate and Potassium Chromate. Procedure: Filtering and using the electronic balance 1.) Obtain a test tube from the test tube rack. 2.) Clean out a Test Tube (TT) with DI water. 3.) Add 3.0 mL of Pb(NO3)2 to the TT. 4.) Add 10 drops of K2CrO4 to the TT. 5.) Observe the reaction. Record your observations on your data table. 6.) Mass an empty filter paper. Put your initials on the outside of the filter paper – using a pencil. 7.) Set up filtration using a funnel, ring stand, ring, and clay triangle. 8.) Filter out the solid which is called the precipitate. Bring filter paper to your teacher to dry overnight. 9.) The aqueous solution which comes through the funnel is the filtrate. 10.) Clean up lab station. Data table: Observations: Mass of Empty filter paper Mass of Filter paper plus solid Mass of solid Questions: 1. What did you observe that indicated a chemical reaction had taken place? 2. Before filtering, the products were what kind of mixture (hetero or homo)? 3. Which elements are in Pb(NO3)2? 4. Classify K2CrO4 as an element, compound, heterogeneous mixture, or solution. 5. The product that you filtered out was a solid called a ____________ 6. Describe the other product (the liquid).