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18.  (WCSU25.[x]) Ice cream begins as a solution of milk, sugar, and stabilizers. This liquid mixture is pasteurized at high temperature (72 oC) to kill any harmful bacteria. The pasteurized solution is cooled, flavors are added, and then it is placed in a “hardening room” (at -38 oC) to freeze.   Cs (solid) = 3.10 J/g·K Cs (liquid) = 1.60 J/g·K ΔHfus = 186 J/g a. (5 points) Draw the cooling curve for ice cream beginning as a liquid at 72 oC to solid at -38 oC. The freezing point of ice cream is -3 oC.  Label the axes with temperature values. (Blank graph given below.))   b.  (8 points) Calculate how much heat (in kJ) must be removed from a ½ gallon (912 g) of Bittersweet Mint when it cools from 72 oC to -38 oC.   Enter the heat lost from the ice cream below:

23. (WCSU25.[x], 6 points) The balanced combustion reaction for methane is shown. CH4 (g)       +       2 O2 (g) 

How did MDMA become popular and openly used in the late 70’s and early 80’s?

The majority of euphoric and analgesic effects of morphine are the result of action at which of the following receptors?

Monoamine Oxidase Inhibitors (MAOIs) act by permanently crosslinking to their targets and yet people must take the drugs on a regular basis because:

24.  (WCSU25.[x]) Strategies to convert methane to methanol may be useful to produce quantities of methanol for use as a fuel alternative to gasoline. a.  (4 points) Write a chemical equation where ΔHf = ΔHrxn for the formation of methanol (CH3OH) b.  (4 points) If the heat of formation of 1 mol of CH3OH is -201.3 kJ, calculate the heat exchanged when 43 g are formed?   Enter the heat calculated in part b below.

20. (WCSU25.[x], 8 points) You are developing a new fluoride-containing mouthwash.  Rather than using NaF, you decide to use SnF2.  This should save money since tin fluoride is cheaper and is shown to prevent cavities in a number of studies. Calculate the mass of SnF2 (MW = 156.69 g/mol) needed to prepare 500 mL of a mouthwash with a 0.01 M fluoride ion concentration? Enter the mass needed below.

Why is naloxone considered a highly effective but short-term treatment for an opioid overdose?

Heroin is converted by the body into morphine, so heroin is known as a(n):

The neurotransmitter systems that are involved in schizophrenia: