Gas stochiometry:
prelab assignment (10 points) due at the begining of lab
purpose
compare the actual mass of Mg to the experimentally determined mass of Mg (in the above reaction)
materials
~15 mm Mg ribbon, ~ 20 mL 6 M HCl, water
eudiometer tube (measures the volume of a gas), thermometer, barometer, 2-hole stopper; pneumatic trough
beaker, ruler, thread (to secure Mg to stopper); balance
methods / data analysis
student design
Content of lab report [30 points]
introduction [5 points]: describe the calculations using equation / formula (); do not use actual values
experimental methods [5 points]
data analysis [15 points] :
- calculation to determine the mass of Mg based on measurements related to H_{2 } gas & % error; show calculations & data table
- statistics (include interpretation of p-value; refer to the purpose of the lab)
- calculate % error (recomend use MS Excel; show screen-shot of output; label appropriately) due to:
- not correcting for water vapor
- not correcting for the height of the column of water in the eudiometer tube
- not correcting for both of the preceding factors
discussion [5 points]
- what is the importance to correct for the preceding factors ? i.e. consequence for NOT correcting for these factors ?
- provide a plausible, nontrivial error (not the preceding factors) to rationalize your results. be specific.
additional resources
table relating the partial pressure of water as a function of temperature
lab activity source (examples): site 1 & site 2 [access 4 / 2009