Design Lab #17: Reaction Rate - Calcium Carbonate & Hydrochloric acid Design D: Introduction: In this experiment calcium carbonate will be put into a flask and mixed with hydrochloric acid to produce calcium chloride, water and carbon dioxide. The formula for this reaction is: CaCO3(s) + 2HCl(aq) > CaCl2(aq) + CO2(g) + H2O(l) Purpose: The purpose of this experiment is to determine how the surface area of CaCO3(s) affects the rate of reaction by measuring the volume of CO2(g) produced with time.
Background: When solid reactants are mixed with liquid reactants only the particles on the surface of the solid will have direct contact, or collide, to the other liquid reactant particles. When there is more surface area there will be more solid particles exposed to collide with other liquid particles. When there are small pieces of the solid reactant, the rate would be faster than if it were larger pieces with the same mass. There will be more collisions per unit of time, which means reaction will precede faster. Variables: Independent (Changed) ) Surface area of CaCO3 Dependent (Measured) 1) Volume of gaseous product formed (CO2(g)) Controlled (Constant) 1) Mass of CaCO3 2) Temperature of reaction 3) Concentration of HCl 4) Volume of HCl 5) Time intervals for recording volume Apparatus: 100 mL Conical flaskSingle-holed rubber stopper 90 g of CaCO3 chips90 g of CaCO3 powder 90 g of CaCO3 tablets100 mL gas syringe 100 mL graduated cylinderDigital Stopwatch 450 ml 1. 0 M HCl Stand & Clamp Electronic balance Safety Procedures: 1) Wear safety goggles for protection. 2) Handle HCl acid with care. If splashes on skin wash immediately 3) Always point gas syringe downwards.
Procedure: 1) Set up equipment for experiment. Set up the gas syringe with the clamp and connecting pipe connecting to the flask. Have the rubber stopper and stopwatch nearby at your station. 2) Place a on electronic balance. 3) Place the CaCO3 tablet on and weigh 10 g precisely on electronic balance. Record mass. 4) When taking mass make sure the tablet, chips and powder all have the same mass; 10g 5) Measure 50 mL of acid with a graduated cylinder. Pour into conical flask. 6) For the first reaction use the CaCO3 tablets. Start stopwatch immediately after CaCO3 tablets are added into flask.
Simultaneously cover flask with stopper. 7) Insure that the connecting pipe from the flask to the syringe is connected properly. 8) At 10 seconds record the volume of gas in the syringe. 9) Record the volume of gas inside syringe every 10 seconds until you have 3 consistent readings. 10) Repeats steps 2 through 8 for two more trials to have 3 values for every type of CaCO3. 11) Repeats steps 2 through 7 for the CaCO3 chips 12) Repeats steps 2 through 7 for the CaCO3 powder. Method: 2. Cut magnesium ribbon into 15 20mm strips ±0. 5mm 3. Fill measuring cylinder with 100ml ±0. 1ml water. Invert inside an ce-cream container. Fill container with water. 4. Take the 5 mol dm-3 acid and pipette 5ml ±0. 1ml of acid into each 3 test tubes. Insert delivery tube into measuring cylinder under water and prepare bung above the boiling tube. 5. Pour one test-tube into the boiling tube. Place one piece of 2cm ±0. 5cm magnesium into the tube, affix bung to the tube and begin the stopwatch 6. After 5 seconds, record the amount of water displaced on the measuring cylinder. This will be in millilitres ±0. 1ml. Repeat this at 10 seconds. 7. Continue recording at 5-second intervals until 3 consistent readings are gained. . Repeat steps 4 through 7 with the other two prepared test tubes to give 3 readings per concentration 9. Repeat steps 3 through 8 with the remaining four prepared concentrations of acid Stat stopwatch Place the marble chips and powdered marble into separate test tubes. Add 10cm of the dilute hydrochloric acid to each of the test tubes and observe the rate at which carbon dioxide is produced Gas Syringe Method Equipment Conical Flask, Bung, Connecting Pipe, Gas Syringe, Hydrochloric Acid, Magnesium Ribbon, Clamp, Stand. For this method we set up the equipment as follows;
The first to do is to gather together all equipment, then once that is done get the conical flask and put the bung into the top of it. Then connect the pipe from the bung to the gas syringe, making sure that it is air tight. Then once everything is set up get the stop clock ready, measure out the 50ml of hydrochloric acid and pour it into the conical flask and again the same as the burette method simultaneously put the magnesium into the conical flask, put the bung into the top of the flask and start the timer. We took down measurements in 5 second intervals. The gas syringe has a volume of 100ml?.
