6) Use the acidity modelpH = log[H⁺]where acidity (pH) is a measure of the hydrogen ion concentration [H⁺] (in moles of hydrogen per liter) of a solution. Compute [H⁺] for a solution for which pH = 5.5. (Round your answer eight decimal places.) ________ moles per liter

7) At 8:30 A.M., a coroner was called to the home of a person who had died during the night. In order to estimate the time of death, the coroner took the person's temperature twice. At 9:00 A.M. the temperature was 85.7F, and at 11:00 A.M. the temperature was 82.9F. From these two temperatures the coroner was able to determine that the time elapsed since death and the body temperature were related by the formula

t = 10 ln (T-70/98.6-70)

where t is the time (in hours elapsed since the person died) and T is the temperature (in degrees Fahrenheit) of the person's body. Assume that the person had a normal body temperature of 98.6F at death and that the room temperature was a constant 70F. Use the formula to estimate the time of death of the person. (This formula is derived from a general cooling principle called Newton's Law of Cooling.) a)3:00 A.M.

b)12:00 A.M.

c)5:00 A.M.

d)4:00 A.M.

e)6:00 A.M.