Jun 19, 2017 · Stoichiometry of a Precipitation Reaction Hands-On Labs, Inc. Version 42-0201-00-02 Lab Report Assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions, diagrams if needed, and data tables that should be addressed in a formal lab report. Experiment 3: Stoichiometry of a Precipitation Reaction. Abstract:In this experiment the objectives were to try and predict the amount of product that was produced in the precipitation reaction of calcium carbonate by using stoichiometry. Then learn how to figure out the actual yield, theoretical yield and percent yield of the experiment. Precipitation. In this experiment, a reaction between the two aqueous reagents copper (II) nitrate, Cu(NO 3) 2, and potassium iodide, KI, will form a precipitate.The same word meteorologists use when talking about falling rain and snow, a precipitate in a scientific sense is the solid formed during a reaction between two aqueous compounds.