Proper chemical formulas entitle many challenges such as the Law of Multiple proportions that states that there may be more than one plausible mole ratio for the elements in that compound. However if we determine the mass of each element in the compound we will be able to get the true chemical formula. In this experiment, we used the law of definite proportions to find the chemical formula for a hydrated compound containing copper, chlorine, and water molecules locked in the crystal structure of the solid compound of Copper Chloride Hydrate. First we will gently heat a sample of the compound to drive off the water of hydration. By measuring the mass of the sample before and after heating we can determine the amount of water in the sample. Second, we will conduct a chemical reaction with the dried sample, which will produce elemental copper. By measuring the mass of copper that forms, we will have the necessary information to determine the moles of copper and chlorine in our sample, and we will be able to establish the proper chemical formula. Objectives:
•Determine the water of hydration in a copper chloride hydrate sample. •Conduct a reaction between a solution of copper chloride and solid aluminum. •Use the results of the reaction to determine the mass and moles of Cu and Cl in the reaction. •Calculate the empirical formula of the copper chloride compound. Material:
•crucible with cover•unknown solid copper chloride hydrate •crucible tongs•aluminum wire, 20 gauge
•spatula•6 M hydrochloric acid, HCl, solution
•ring stand, ring, and clay triangle•95% ethanol solution •lab burner•distilled water
•50 mL beaker•wash bottle
•Büchner funnel and filter flask•balance
•filter paper to fit Büchner funnel•glass stirring rod •watch glass•heat lamp or drying oven
1.Wear goggles for Safety purposes.
2.Measure and record the mass of a clean, dry crucible without cover. Obtain about 1...