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20 Computerized Data Analysis 2. Do you expect the contribution of the water vap

ID: 485978 • Letter: 2

Question

20 Computerized Data Analysis 2. Do you expect the contribution of the water vapor in the collected hydrogen gas to be higher or lower at higher temperatures? Explain your reasoning by referring to the motion water molecules. 3. At 20°C, the vapor pressure of the water is 17.54 mm Hg. If you are collecting your hydrogen gas at atmospheric pressure of 738 mm Hg at this temperature, what is the pressure (in mm Hig) of hydrogen gas in your collection tube? 4. If you collect 310.0 mL of hydrogen gas under the conditions above, what is the mass (in g) of hydrogen gas you were able to produce by electrolysis? 5. Now that you have overcome the challenge ofcollecting the hydrogen gas for fuel, another concern is working with it carefully, due to its highly flammable nature. Look up the Firefighting Measures Section of the SDS for hydrogen gas. If the gas does catch on fire, what media is suitable to put it out?

Explanation / Answer

2.Temperature is increases kinetic energy of molecules are increases.

molecular motion of hydrogen molecules are increases with temperature.

3. atmosphric presure = 738mmHg

   water vapour pressure = 17.54mmHg

   H2 gas pressure           = 738-17.54 = 720.46mmHg

4. T = 20C = 20 +273 = 293K

   P   = 720.46/760   = 0.948atm

V = 310ml = 0.31L

PV   = nRT

PV = WRT/M

W    = PVM/RT

         = 0.948*0.31*2/0.0821*293 = 0.0244g