Introduction. In this experiment the mass of zinc on galvanized iron nails was calculated to determine the appropriate price that should be charged to coat a nail with zinc (galvanize) it. The effectiveness of gasometric and gravimetric analysis were assessed by carrying out both methods mathematically using values determined by this experiment, and then comparing these values using their percent differences. The mass of zinc found on each nail can then be used to determine how much it should cost to galvanize 100 nails considering zinc cost $2.86/kg.
Experimental Procedure. Three nails were ascertained and then weighed to the nearest 0.0001 grams. A 100 mL graduated cylinder and a 600 mL beaker were then submerged underwater. While this took place the graduated cylinder was placed upside down in the beaker. The two items were then removed from the water, and the graduated cylinder was clamped upside down in the beaker. A rubber stopper with two holes in it was then placed in a 125 mL Erlenmeyer flask. A rubber tube was then inserted into one of the holes of the flask, with the other end in the upside down beaker. 20 mL of air was then pumped into the graduated cylinder. About 20 mL of 6 M HCL was then added to the flask. A nail was then inserted into the second hole in the stopper, followed by a glass plug. Immediately after the reaction [Zn(s) + 2 H3O+(aq) à Zn2+(aq) + 2 H2O(l) + H2(g)] was stopped, the nail was removed and rinsed. Once the nail dried, it was massed and disposed of. Water was then added to the beaker until its level matched that in the graduated cylinder. The amount of hydrogen gas that was released in the reaction was measured in the graduated cylinder. This was repeated for the other two nails.
Data/ Results. Gravimetric analysis was performed by subtracting the mass of the nail after the zinc was removed from the mass of the original galvanized nail. This gave an average of