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An operator loses his job at the refinery and decides to supplement his income by free-basing cocaine with drain cleaner and selling at a mark-up while he looks for another job (no, I am not advocating anything like this, just thought it would make for a fun and interesting exam question).  He is able to procure [m] grams of cocaine as the hydrochloride powder (molecular weight = 339.6 g/mol) and finds that [vbase] mL of drain cleaner (NaOH) from the hardware store can be titrated with [vacid] mL of [Macid] M muriatic acid (HCl) from the pool supply center.  What volume of drain cleaner should he use to convert his powder cocaine into crack?  Report your answer in mL.  As usual, no units needed, just report the number of mL. cocaine_crack.png 

Calculate the number of atoms in [x] grams of magnesium.  You will probably need to use exponential format on this one — your answer should look something like 1.23e56, where the e takes the place of “x 10^” in scientific notation.

The outer shell of an atom is known as its 1) ________________ shell.

A winch driven by a gasoline engine is used to lift a piece of heavy equipment onto a platform, doing [w] Btu of work on the equipment.  If the engine used [g] gallons of gasoline, with an energy content of [b] Btu per gallon, how much energy was lost to heat?  Give your answer in Btu, but do not include units in your answer.

Which of the following statements are true?  Choose all that apply.

A team of engineers and operators are bringing an alkylating unit into production for the first time.  The reaction converts toluene to propylbenzene by reacting it with ethylene according to the following reaction: toluene2propylbenzene.png After reacting, the product is piped over to a distillation unit, and the distilled product is stored in a storage tank.  If the team converts [t] pounds of toluene to product and collects [p] pounds of propylbenzene in the storage tank, what was the percent yield of the process?  You do not need to include a percent sign in your answer, just the number. (Hint:  the molecular weights of toluene and propylbenzene are given in the picture describing the reaction.  If you are clever about it, you don’t need any more information or to do any stoichiometry to find the answer.  You can still solve it with stoichiometery, but it will take a bit longer…)  

Calculate the energy required to heat [w] grams of water by 15°C.  Give your answer in Joules (units not required in the answer.)  The specific heat of water is 4.184 J / (g • °C).

Match the name with the formula for the following compounds.  Some formulas will not be used.

Choose the best answer to fill in the blanks of the passage.  Some answers may be used more than once, some may not be used. 1)__________________________ allows the determination of a quantity of a product or reactant in a chemical reaction equation on the basis of a given quantity of a different product or reactant.  In such a calculation, a mass can be converted to a(n) 2)_________________ by division by the molecular weight of the compound, then the ratio to a different compound involved in the reaction determined using the coefficients of the reaction equation.  However, in some cases one reagent may be a(n) 3)________________, such that there will not be enough of this material for the other reagents to completely react.  In such a case, the other reagents will be 4)______________________, and there will be some left over once the reaction is complete.

Atoms usually achieve a stable outer shell through ______________________ and/or _____________________________.