b Punch a hole in the middle of the aluminum foil with a pencil Then slide the

B punch a hole in the middle of the aluminum foil

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b. Punch a hole in the middle of the aluminum foil with a pencil. Then slide the temperature probe through the aluminum foil. This will be used to cover the Styrofoam cup. c. Nest the Styrofoam cup in a 400 mL beaker to avoid spilling. Add the magnetic stir bar and place on top of the stir plate. 2. Measure 25 mL of 2.0 M HCl solution with a graduated cylinder. Pour solution into the Styrofoam cup, lower the temperature probe in the solution and cover the opening of the cup with the aluminum foil. Stir the solution for three minutes. Record this temperature as the initial temperature. 3. In the meantime, measure 25 mL of 2.0 M NaOH solution, but do not add it to the HCl solution yet. 4. Start the Lab Quest, then add the NaOH solution. Cover properly with the aluminum foil. 5. After 3 minutes, record the maximum temperature observed on the LabQuest on your data sheet. 6. Calculate ΔH rxn . 7. Rinse and dry the temperature probe, Styrofoam cup, and the stir bar. Discard of solution in the waste beaker. 8. Repeat the procedure above using your other calorimeter as a second trial. Reaction between NaOH and NH 4 Cl NaOH(aq) + NH 4 Cl(aq ) → NaCl(aq) + NH 3 (aq) + H 2 O(l) 1. Measure 25 mL of 2.0 M NaOH solution with a graduated cylinder. Pour solution into the Styrofoam cup, lower the temperature probe into the solution, and cover the opening of the cup with the aluminum foil. Stir it for three minutes. Record this temperature as the initial temperature. 2. In the meantime, measure 25 mL of 2.0 M NH 4 Cl solution, but do not add it to the NaOH solution yet. 3. Start the Lab Quest, then add the NH 4 Cl solution. Cover properly with the aluminum foil. 4. After 3 minutes, record the maximum temperature observed on the LabQuest on your data sheet. 5. Calculate ΔH rxn . 6. Rinse and dry the temperature probe, Styrofoam cup, and the stir bar. Dispose of the solution in your waste beaker.
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