A crime has occurred at a local factory that produces sterile saline (NaCl) solution for commercial use in hospitals and for consumer use as a cleaning agent for contact lenses. An employee was found floating in a vat of liquid in the factory. It’s been determined that the man was pushed into the tank but there is no evidence of water in the lungs to indicate the man drowned. The detectives on the scene suspect that the man ultimately died from an electrical short that occurred when a loose wire contacted the water. A torn electric cord hanging from the ceiling suggests the victim may have tried to use it to pull himself out of the vat when it broke. Your critical brain knows that the answer to that question lies in what exactly was in the vat. Q1: Think about the liquid in which the man was found floating. Why is it unlikely that the man died from an accidental electrical short if he was found in a vat of distilled (pure) water? Why would it make a difference if the man was found in a vat of saline solution (NaCl dissolved in water)?
Q2: The vat is made of metal. Why might it matter that the material from which the vat is made is metal?
Q3: Upon closer investigation, it’s found that the vats are coated on the inside with a thick plastic lining. Plastic is made from hydrocarbons – molecules containing carbon and hydrogen. How does this finding affect your explanation about the nature of the man's death?