A woman is found dead on a boat floating in the middle of a lake at 4:30am. There is blunt force trauma to her head but no other discernable damage. She is approximately 30 pounds overweight. She is wearing thermal clothing and a winter jacket, gloves, and hat. Climatological data indicate it was a clear, cold, and windy night with no precipitation. Calculate the time of death based only on a body temperature of 15.6°C (60.8°F)? Now consider the other factors presented. How would each affect this estimation?

Answerthis solution will not form a precipitateexplanationsolubility equilbrium:         pbf₂(s)  ⇄ pb²⁺(aq) + 2 f⁻(aq)the solubility product expression is    (we exclude solids from the equilibrium expression).now suppose we have the trial ion product q, which we can define as    then, we can interpret  q as the product of the concentration of the ions that we have and ksp as the product of the ion concentrations that are needed to form a saturated solution.if q > ksp, then that implies that there will be a surplus of ions that exceed the amount that is required to form a saturated solution. a precipitate will then form (the precipitate continually  forms until the surplus ions are removed and q is decreased to ksp's value).if q = ksp, the saturated solution that forms is barely saturated and the precipitate will be minimal.if q < ksp, then the ion concentration will not be enough to form a saturated solution (so no precipitate).using our information, we calculate the trial ion product:     since q = 2.7  × 10⁻⁸ < ksp =  4  ×  10⁻⁸, a precipitate will not form.