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B. Prelab Questions: A reaction of 0.028 g of magnesium with excess hydrochloric acid generated 29.0mL of gas. The gas was collected by water displacement in a 22C water bath. The barometric pressure in the lab that day was 746mmH. 1. Use Dalton's law and the vapor pressure of water at 22C (Table 1) to calculate the partial pressure of hydrogen gas in the gas collecting tube. 2. What is the theoretical number of moles of hydrogen that can be produced from 0.028 g of Mg ? 3. Calculate the ideal gas constant (R). Comment on the value of R Teable 1. Vawor Prenatere of Mafer at Dufferment Tenwoenaturen C. Procedure: Write the procedure used for this experiment in your own words. D. Results and Calculation: Data Table 1: Measured Values: Data table 2: Calculated Values 1. Calculate the theoretical number of moles of Hl(g). Trial 1 Trial 2 2. Calculate the partial pressure of H2(g) produced. Trial I Trial 2 3. Calculate the value of the ideal gas constant (R). Trial 1 . Trial 2 E. Discussion: 1. Write the chemical reaction occurring in this experiment. 2. How is your value of R related to the exact value? 3. After weighting the Mg ribbon, a student noticed that it is oxidized. Student A decided to continue the experiment without cleaning the ribbon. Student B decided to clean the Mg ribbon before doing the experiment. For both Student, discuss the effect of the source of error on the value of R (Would the calculated constant R be too high or too low?) F. Conclusion: G. Reference