On Thursday February 23, 2012, we completed a Chemistry lab called Ion Combination which involved mixing solutions, solving out double replacement reaction equations, and net ionic equations. While completing this lab I was not surprised by any of the reactions and how precipitations were formed because I have completed a lab like this in AP Chemistry at my high school. Our lab consisted of solutions that were unlabeled and we had to combine the solutions and analyze the precipitates formed to figure out what we were mixing due to products of the reaction. An observation that led me to believe a chemical reaction was occurring is that a precipitate had formed. There were also color changes that occurred when mixing the two solutions together. These are sure signs that a chemical reaction has occurred. Also when we used the molecular substances and combined those, a chemical reaction had occurred because there was a temperature change and a gas had formed; both of which are another way of knowing that a chemical reaction has occurred. When combining solutions, there were reactions that produced different product states.  Different product states would include when two liquids were combined to form a solid precipitate. Another would include when we combined the two solutions and a gas developed. All of these observations we can conclude from this Ion Combination Lab. When sodium chloride (NaCl) is added to water (H20), the sodium and the chloride dissociate from each other resulting in sodium + ions and chloride - ions. The chemical disassociation equation would be:
NaCl -> Na+ + Cl-