SHOW SET-UP FOR ALL PROBLEMS

A student collected 130.2 mL of hydrogen (H2) over water at 752.8 torr atmospheric pressure and 17.7 °C. The mass of Zn metal used to generate the H2 was 0.387 g.

1A. (1) Use the table in Appendix B and the method of interpolation to determine the vapor pressure of water at 17.7°C. (2) Use Dalton's Law to calculate the partial pressure of H2 in the experiment.

1B. Convert the experimental volume of dry hydrogen measured under the conditions above to the volume that would have been observed at STP (0 °C and 760 torr).

1C. Write the balanced net ionic equation for the unbalanced molecular Equation 5.

1D. Calculate the number of moles of H2 gas from the mass of Zn metal used. Calculate the molar volume (L/mol ) of hydrogen at STP from the data above (Equation 5). Determine the percentage error in Vm. (The accepted theoretical Vm is 22.414 L/mol at STP). (Use extra page if necessary).

2. A certain mass of gas has a volume of 247 mL at 85.3°C. Calculate the theoretical volume that this gas would occupy at 15.2°C and the same pressure.

3. Suppose that the Zn metal piece had "rusted" forming a gray coating of ZnO (zinc oxide) prior to weighing the metal. The ZnO would then react with the HCl(aq) according to the following unbalanced molecular equation:

ZnO(s) + HCl(aq) ----> H2O(l) + ZnCl2(aq)

a. Write the balanced net ionic equation for the reaction above.

b. How would the ZnO coating affect the Experimental Molar Volume (EMV) of H2 gas? (Increase EMV, Decrease EMV, Not affect EMV) Explain.