Net Ionic Equations and Spectator Ions

In 2007, nearly thirty-nine thousand pets in America became sick after eating their daily bowls of food. Officials were unable to link the illness to any one brand of food, because almost one hundred different brands of food were involved. Chemistry came to the rescue. Scientists were able to narrow down the possibilities to just two contaminants in the pet food; both of which were found in the imported wheat gluten that was used in the dog and cat food. The chemists performed many tests with the two substances. They found that when the two substances were combined in the same environment they mimicked the kidneys of the pets. The combination of the two substances produced a mysterious crystal that precipitated out of solution. Upon further analysis, this crystal was determined to be the culprit that was making the animals sick. By themselves, the two substances were considered quite safe. When put together in an aqueous solution and just the right pH, they chemically combined in the kidneys of animals. Sixty million cans of dog food were recalled immediately. Without a good knowledge of chemistry and what happens to ions in an aqueous solution, this mystery would never have been solved.