Empirical Formula of Iron Oxide & Hydrate Labs
Use this page to discuss questions and results for the two labs.

In the Rust Lab the ammonium chloride solution is used to accelerate the rusting process. It was chosen because it is a good electrolyte (it facilitates the motion of electrons between chemical reactants) and because it can be driven off at high temperatures, leaving essentially no trace.

Common problems:
Rust Lab:
Not all of the steel wool rusts so the measured amount of oxygen is less than it should be.
Not all of the ammonium chloride is driven off so the measured amount of oxygen is more than it should be.

Hydrate Lab:
If not all of the water is driven off then the ratio of water to anhydrous salt will be too low. This can happen
if the hydrated salt is dehydrated around the edges of the crucible but not in the middle.
If you cause the salt to decompose then the ratio of water to salt will be too high. Work out for
yourself the quantitative reason for this.
Subject Author Replies Views Last Message
No Comments