Assignment:
Add 0.25g of zinc to the Erlenmeyer flask and close the flask with an air-tight stopper. Take a thermometer and pressure gauge and record the initial temperature and pressure.(my answer: 21C, 1 atm). Add 10 mL of 6M HCl solution to the flask. Record all of the indications that the reaction has occurred (my answer: temperature above 30C, 1.729 atm). Once the flask has cooled down to room temperature (21C), drop the flask onto the gas piston. This connects the two and allows gas to flow from the flask into the gas piston until the pressure equalizes. What pressure is that (my answer: 1 atm?) Record the volume of gas that is contained in the gas piston (my answer: 102.14mL )
Repeat the experiment with a new flask and gas piston, using 0.5g of zinc and 10 mL of HCl. Record all of the indications that the reaction has occurred (my answer: temperature above 40C, 2.386 atm). Drop the flask onto the gas piston to allow gas to flow from the flask into the gas piston until the pressure equalizes. What pressure is that (my answer: 1 atm?) Record the volume of gas that is contained in the gas piston (my answer: 194.28mL )
Q1. Record and calculate the following for the first half of the experiment:
(a) Mass of zinc used (g): 0.25g
(b) Volume of 6M HCl used (mL): 10mL
(c) Molecular weight of zinc (g/mol): 65.39g/mol
(d) Moles of zinc reacted: 0.0038 moles
(e) Moles of hydrogen produced: 0.00382 moles
(f) Molar volume of the ideal hydrogen gas at room temperature (Volume/moles), expressed as L/mol at X degrees C and a pressure of 1 atm.
Q2. For the second part of the experiment, everything was the same except that twice as much Zn was used.
(a) Mass of zinc used (g): 0.50g
(b) Volume of 6M HCl used (mL): 10mL
(c) Molecular weight of zinc (g/mol): 65.39g/mol
(d) Moles of zinc reacted: (just half will react?)
(e) Moles of hydrogen produced: (is it the same as in the first experiment?)
(f) Molar volume of the ideal hydrogen gas at room temperature (Volume/moles), expressed as L/mol at X degrees C and a pressure of 1 atmosphere.
Q3. Compare the molar volumes obtained in the two parts of the experiment. What difference did using twice the amount of Zn in the second part? Was all of the zinc used up in the reaction? Which is the limiting reactant - zinc or HCl?
Q4. Compare the experimental value for the molar volume at 21C with the accepted value. Calculate the experimental error according to
% error = | experimental molar volume - listed molar volume | / (listed molar volume) * 100
Provide complete and step by step solution for the question and show calculations and use formulas.