Checking answers

Look over the entire exam work questions that you are sure of then go to less sure questions check answers if time permits. 

Every effort has been made to make this Solutions Manual as clear, attractive, and error-free as possible. Nevertheless, you should use the Solutions Manual in moderation. The principal use of this book should be to check answers to problems you have already worked out. The Solutions Manual should not be used as a substitute for effort at times, struggling with a problem is the only way to teach yourself. 

In the open-book paper of the registration exam, save time by not looking up questions to which you think you know the answers. If you have time at the end of the exam, you can then check answers in the reference texts. 

Many students check Answer b as being correct and, again, exhibit the expected misconception in their explanation, i.e. at equilibrium, the concentrations of all involved substances are equal [7] ... 

If you chose to live in a radiation-proof home to escape radiation originating from outer space, you would still have to contend with the radiation that is naturally in your body. If you weigh 150 pounds, you have about 225 grams of potassium ions in your body. Potassium ions participate in nerve conduction and the contraction of muscles, including the heart. Without potassium ions, you don t live. The natural abundance of is 0.0118% of all potassium ions. A 150-pound person therefore has about 4.1 X 10 ° radioactive i°K atoms in his or her body. (You might like to confirm this statement by calculation. We ll show the calculation setup after the Target Check answers.)... 

Oliver may agree with everything, either because he wants to please you, or is embarrassed to say he doesn t understand. Avoid leading questions (e.g. You re not suicidal, are you ), and double-check answers by asking the opposite question, e.g. 

Redhead [89] gives the approximate equation EjRTm - ln(A7) //3)- 3.64. Check the usefulness of this equation by comparing with the answers to Problems 5 and 6. 

Problems with several published solutions This section gives you some real problems which have akesdy been solved by several different routes. You can check your answer against these published routes. 

Identify the longest and the shortest carbon-carbon bond in styrene and check your answer by making a minimized molecular model using Learning By Modeling... 

Before accepting this answer, we check to see if our approximation was reasonable. In this case the approximation 0.10 -l-x 0.10 seems reasonable since the difference between the two values is negligible. The equilibrium concentrations of Pb3+ and IO3-, therefore, are... 

When you obtain your final answer, be sure to check your assumptions. If any of your assumptions prove invalid, then return to the previous step and continue solving. The problem is complete when you have an answer that does not violate any of your assumptions. 

Before accepting this answer, we first check our assumptions. Using the Ksp equation we calculate the [Ag+] to be... 

Checking Against Optimum Design. This attempts to answer the question whether a balance needs to be as it is. The first thing to compare against is the best current practice. Information is available ia the Hterature (13) for large-volume chemicals such as NH, CH OH, urea, and ethylene. The second step is to look for obvious violations of good practice on iadividual pieces of equipment. Examples of violations are stack temperatures > 150° C process streams > 120° C, cooled by air or water process streams > 65° C, heated by steam t/ urbine 65% reflux ratio > 1.15 times minimum and excess air > 10% on clean fuels. 

Check the answers and examine the sensitivity of the result to changes in the coefficients in the problem and the assumptions. 

The pumped-discharge case is generally more difficult to solve because of the uncertainty in deahng with negative numerical results. As a final answer, a negative value could indicate that the pump has completely emptied the tank however, as an intermediate value, it could mean that it is not a true solution. A simple check is to try a different initial estimate and see if the intermediate negative results disappear. 

Answer this question only after you have completed the rest of the report. The specific identity of the toxic chemical being reported in Part III, Sections 1.2 and 1.3, may be designated as trade secret. If you are making a trade secret claim, mark yes" and proceed to Section 1.2. Only check "Yes" if it is your manufacturing, processing, or use of the chemical that is a trade secret. (See page 1 of these instructions for specific information on trade secrecy claims.) ff you checked "no," proceed to Section 1.3 do not answer Section 1.2. 

Answer this question only after you have completed the rest of the report. Check "sanitized" if this copy of the report is the public version and you have claimed the chemical identity trade secret in Part I, Section 1.1. Otherwise, check "unsani-tized."... 

Pyridine is a flat, hexagonal molecule with bond angles of 120°. It undergoes substitution rather than addition and generally behaves like benzene. Draw a picture of the 7T orbitals of pyridine to explain its properties. Check your answer by looking ahead to Section 15.7. 

The following answers are meant only as a quick check while you study. Full answers for all problems are provided in the accompanying Study Guide and Solutions Manual. 

Reelity Check You can use the periodic table to check your answer. See Figure 6.9 and the accompanying discussion. 

Reality Check Check these answers against Figure 6.13 and 6.15. 

Reality Check This is a quite reasonable answer as shown earlier, a 0.10 Af solution at 25°C has an osmotic pressure of 2.4 atm. 

Reality Check In (b), reducing the amount present to 15% takes more time than two half-lives (i.e., more than the time to reduce to 25%). The answer is larger than 2(6.60 X 103), as it should be. In (c), the rate is dependent on the initial concentration, unlike the half-life in (a)—which is independent of the initial amount... 

Reality Check To check the answer in (a), use the calculated concentration to determine Kgpi... 

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