A storage tank for liquid n-octane has a diameter of 30 ft and a height of 20 ft. During a typical 24-h period the level of liquid octane falls from 18 ft to 8 ft, after which fresh octane is pumped into the tank to return the level to 18 ft. As the level in the tank falls, nitrogen is fed into the free space to maintain the pressure at 16 psia; when the tank is being refilled, the pressurt; is maintained at 16 psia by discharging gas from the vapor space to the environment. The nitrogen in the tank may be considered saturated with octane vapor at all times. The average tank temperature is 90F. (a) What is the daily rate, in gallons and Ibm, at which octane is used? (b) What is the variation in absolute pressure at the bottom of the tank in inches of mercury? (c) How much octane is lost to the environment during a 24-h period? (d) Why is nitrogen used in the vapor space of the tank when air would be cheaper?
Alexis Penny th September 16 , 2015 Experiment #03 Determining Avogadro’s Number CHEM 1315-077 Penny 1 Purpose of the Experiment & Techniques: The purpose of this experiment is to confirm Avogadro’s number through electrolysis. A copper strip and a zinc strip will be used as the electrodes, the copper strip as the anode and the zinc strip as the cathode, and put into a beaker of sulfuric acid to make the cell electrolytic. By determining the average current used in the reaction, along with the knowledge that all of the copper ions formed are the 2+ cations, the number of atoms in one mole of copper can be calculated and compared with Avogadro’s number.
