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Empirical Formula Lab - Chemistry. When Powder X is added to hydrochloric acid (HCl) in a water solution, a chemical reaction occurs resulting in carbon dioxide (CO 2 ), given off as a gas, and dissolved calcium chloride salt (CaCl 2 ) and water (H 2 O) in the water solution.
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When Powder X is added to hydrochloric acid (HCl) in a water solution, a chemical reaction occurs resulting in carbon dioxide (CO2), given off as a gas, and dissolved calcium chloride salt (CaCl2) and water (H2O) in the water solution.
Start with a clean 500 mL Erlenmeyer flask Mass the flask and record.
Mass a 500 mL graduated cylinder. Record. Measure out approximately 300 mL of 1 M HCl in the graduated cylinder. Record the exact volume of the HCl. Mass the cylinder and the HCl. Record. Subtract the mass of the cylinder from the mass of the HCl ad cylinder to find the mass of the HCL. Record.
Pour the HCl into the flask. Rinse out the cylinder and place in the drying rack.
Place a plastic weighing boat on a scale and zero the scale out.
Slowly add Powder X on top of the boat until you have as close as possible to exactly 10.009 grams of Powder X. Record exact mass.
SLOWLY and carefully pour the Powder X into the hydrochloric acid. It will fizzle and foam just like vinegar and baking soda so pour slowly or else it will overflow and spill. Spillage negates the experiment and you will have to start over. You will only get one do-over and then you get a zero for the lab.
After ALL the Powder X has dissolved (disappeared), mass the flask and liquid in it. Record.
Put your groups name on the flask with a grease pencil and give the flask and liquid to the teacher. The teacher will carefully boil off the water from the solution and there will be a dry salt sample at the bottom of the flask when the flask is returned to you.
Mass the flask and the salt. Record Subtract the mass of the flask and the salt from the mass of the flask, salt and water before giving flask to teacher. This is the amount of water removed. Record. Take the mass of the flask and the salt and subtract the mass of just the flask to find out the mass of the salt that was produced. Record.
Rinse the flask out in the sink (the salt can go down the drain) and place the flask in the drying rack. Then start having FUN with stoichiometry!
Using your recorded data, figure out what the empirical formula for Powder X might be (you must show all your figuring and stoichiometry that you used). Then figure your percent yield for the CaCl2 salt. Finally, for your experiment show numerically if there was a limiting reactant that may have caused a percent yield other than 100%. You have to show me with your figuring – I’m not going to assume anything!