value table. The presentation was clear and exact. However, two incorrect responses to a question on side two solicited the correct answer and the phrase "we're making good progress". The students found this unit satisfactory. The ark (mole) unit joins together the information from the previous study units. An ork (nonchemical mole equivalent) is 2M) slices of a reactant (bread, cheese or ham). The presentation is accurate and reflects a classroom lesson. Comments from the student users varied from "one more thing to know (ork)," to "there should he more mole problems". In the tutorial section, one mole each of nitrogen, hydrogen and ammonia is represented by three hoxes of different heights. No relationship between the relative masses of the molecules and the respective heights of the boxes can he established because mass has not yet been introduced. Such a representation may he a little premature. However, the student users did not question this representation. The students found bath the sandwich analogy and the chemistry section of this study unit equally difficult. Program structure eontrihuted to their difficulty in that sequential wrong answers resulted in termination of the study unit. Additional remediation in this unit would have been helpful. The students should have been channeled to the beginning of the study unit rather than out of it. The final two study units, ork-slice (molemolecule) and ork-gram (mole-gram), represent a classical presentation of the subject matter with problems similar to those usually discussed in a classroom. The mole-molecule unit has a very good section on scientific notation which was most useful to the students. There was some mishandling of user input as noted a t the beginning of the review. The author reintroduced bores of different heights to represent one mole each of nitrogen, hydrogen, and ammonia in the mole-gram study unit. There was no discussion of the relationship between the heights of the hoxes and the respective molecular masses. According to the estimates of this reviewer, other things heing equal, the heights ofthe hydrogen and ammonia hoxes need to be reduced approximately 30 and 9 percent, respectively, relative to that of nitrogen, for proper representation. The last two sections of this tutorial enjoyed a favorable reaction from the student users. There are four self-test units, two for each part of the disk. Each self test covers three study units and consiste of three questions for each unit. There is no remediation. A short buzzer-type saund Indicates an incorrect response and a short happy sound praises a correct response. The questions adequately reflect the suhjectmatter in both depthand difficulty. The students need to understand the subject matter of the tutorial to answer the questions correctly. The overall presentation of the information is good. Definitions and explanations are available when necessary. The progression of the presentation is logical and weUidentified. The problems are relevant at the point of instruction. Students who completed their first year of chemistry found the package relatively
esay. They would have preferred that the author spend more time on chemical storchiometry and to present a greater variety of prohlems. Students taking their first course in chemistry experienced same difficulties with the oackaee. The inahilitv to move within a &en .. siudv unit and tb look a t a previous page of information, the automatic branching out of the study unit, and the need for more remediation were their primary difficulties. Discussions with the above student users seem to indicate that the package is most suitable for students enrolled in a second course in high school chemistry or those in first-year college chemistry.
Frank Montagnino Cardinal Spellman High S c b l 1991 Needham Avenue Bronx. NY 10466
use, similar to those found in most romplete laboratory manuals, would be a useful addition to the package. The program is divided into fourmodules. A well done graphic illustration of an experimental set up illustrates the "experiment" being done. The illustrations are especially nice with a color monitor, but monochrome is certainly acceptable. In the three modules on the solubility behavior of solids in liquids the illustrstion is of a beaker containing solvent to which small portions of solid are added. When the saturation limit is reached solid material appears on the bottom of the container, and the data display tells the amount of solid which has dissolved, and the total amount which has been added. The space bar "pushes" portions of solid from a ledge above the container into the container and the mixing of the solid with the solution is accompanied hy s short saund. The fourth module, illustrating the mixing of two liquids, is illustrated by two spigots aver aeontainer. When the "experiment" is started the spigots turn and liquids flow into the container. The spigots turn off and time is allowed to oass to determine if the liauids mix or not. Buth illustratima are good, and students responded positively to them. What they are depicting is cleat, with m e exception noted below. In the first module portions of a known solid are added to 100 g of water after a temperature has been chosen (in 10 degree intervals from 10 "C to 70 'C). I kept expecting the up and down arrow keys to adjust the temperature, but the left and right arrow keys are the correct ones. After four points have been recorded, the program plots the data on the screen and displays the known soluhility curve on the same plot. A short quiz follows to test student understanding of what has just been done. One question asks the student to decide if the solubility decreases, remains the same, increases slightly, or increases substantially as temperature increases. There are no criteria given to decide the difference between in-. creases slightly and increases substantially. I t is frustrating to know that the soluhility increases with an increase in temperature and also to he told that your answer is incorrect because the program has a slightly different definition from that which you have learned. A potentially confusing question on the quiz asks for the solubility of the compound at a particular temperature. The student is shown the data that has been recorded, even if it is incorrect, hut the only answer that is accepted as correct is the one that the student should have recorded. The program includes an option to print the data and olot. which is useful for notebook records. Yhe'printed plot shows the recorded data and nut the known solubility rurve, whirh can be misleading if mistakes have b e ~ n made in recording the data. In the second module, a computer chosen unknown is the suhject of a soluhility determination as in the first module. After the data are collected and the plot is drawn, the student is asked to ideutifv the unknown hv comparing its data with that in the distributed solubility table or its solubility curve uith the distributed solubility curves. The
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Solublllty Richard Halloren. Educational Materials 8 Equipment 60..old Mill Plain Road. P.O. Box 2805, Danbury. CT 06813
Hardware: Apple II famlly Components 1 dlsk and 1 backup, Study Guide Level and Sublect: High school and introductory c o l l e g e chemistry
cost: $44 Summary RatlwS:
-11 Reviewer Revlewer
c*esory Ease01 Uw: SubjeclMatta content: Pedagogic
Value:
mod
Average
Good
Good
Good
Below Average
Student Reactlon
Revlew Solubility is intended to supplement Ishoratory experience in solubility determination. I t would he useful in high school and introductory college chemistry courses. I t will he most useful if students have had direct laboratory experience, hut it could also he used followine ..demonstrations hv the instrurtor if time or farrlitiesare limited. The provam rs an a single ropy.pnmcted dirk with s harkup. A Study Guide cuntaining a brief overview, hackpouud information, description of the procedure for each of the simulated experiments, and a set of worksheets to he copied and distributed to students accompanies the disk. Permissioh is given to copy only the worksheets and the soluhility tables and curves. Teachers will find that they either must he readily available for instruction or that they must write out their own description of experimental procedure. A more detailed statement of theory and procedure intended for student ~~
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Volume 66
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Number 1 January 1969
A43
would be effective in giving students more exposure to the topic. Frank W. Darrow lthaca College Rhaca, NY 14850
identification is straightforward, and if the student should answer incorrectly twice then the program gives the correct answer. The third module examines supersaturation. The student selects a compound with known solubility at a high temperature, adds compound to solvent to make a nearly saturated solution, and then lowers the temperature (the temperature can he lowered, but not raised, at any time-a frustration if you are not prepared for it). Addition of one more portion of solute causes precipitation of solute and an adjustment of the data display to reflect saturation at the lower temperature. The Study Guide's discussion of supersaturation is brief, and the implications of this module need considerable instructor enolanation. The final muduleisasimulationof mixing one of tour liquids, ethylene glycol, carbon tetrachloride, gaddine, ,,r alcohol, with an equivalent portion of water. The graphic illustrates the mixture during a ahon time after theinitial mixingand then thestudrnt is askpd to decide whether the liqurdr are miscible or not. The separation into immiscible layers isquite clear, but the meaning of what happens with the graphic when the liquids are miscible is unclear. There is something happening on the screen, some changes are #rhser\,ed,but there is noseparation. What are those changes? My experience is that alcohol and water immediately mix to form a solution in which I cannot observe any changes. A student commented that she would have had a hard time deeiding the proper answer to the miscibility question in this instance if she did not already know the answer. The operation of the program is gwd. No computer experience is necessary. I was able to hang it up occasionally, but it rebooted without s oroblem. The prompts are clear and appropriate. Once data has been entered it cannot be chaneed easilv (althoueh it u,ill self.edlt by replacement in some rir. rumstances) and there are trmes when the ability to gu hack a single step instead uf several steps would have been useful, but the "experiments" are short enough that repeating them is not particularly frustrating. There are no problems if the directions are followed carefully. If the directions are not followed then the program does allow the student to do some silly things, hut so does a genuine experiment. Solubility eould easily be used with a class unit on soluhility. I t reinforces end clarifies several soluhility concepts. The Study Guide is too simplistic for thorough understanding, but it can he augmented with standard text readines. Instructors will need to explain carefully how student8 are to proceed and they will need to help interpret results, hut studrnts will qurckly learn how to respond to the computer prompts. Solubility will help in elementary understanding of the soluhility of solids in water, and of some liquids in water, and supersaturation. As stated inthe Study Guide, it is not intended to replace experiments, hut it ~
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Journal of Chemical Education
Solubilil) by Richard Hallgren cmtains four laboratory simulation modules dealing with varicms aspects of soluhility. The first module is a simulated experiment to determine the quantity of a known solid that can dissolve in 100 g of water a t various temperatures. The user may choose one of four compounds. The student adds the compound to water and watches for the point where excess solid begins to accumulate in the bottom of the beaker. Data is collected a t four temperatures and the computer generates a solubility curve graph. The second module asks the user to identify an unknown compound. The simulation and data collection is exactly the same as in the first oroeram. After the comnuter eener,. . ares a graph, the student chooses the identity of the compound from tahles and r,r graphs provided a8 resource mater~als. The third program investigates supersaturation. The student selects one of four compounds about which he knows solubility information. He is instructed to selects high temperature and to add aolute to a point just helow the maximum soluhility. Then he is instructed to lower the temnerature im. mediately and add one more pellet of the compound. At this point he will observe all the excess solute coming out of solution. The purpose of the last program is to establish the miscibility or immiscibility of four liquids (ethylene glycol, carbon tetrachloride, gasoline, and alcohol) with water. Upon selecting the liquid, the student watches to see whether it mixes with water. A Study Guide comes with the cmnputer disk.The Stndy Guide includes an overview of the lessons, a list of ohjectives, hackground material, experimental procedure, worksheets for the students to fill in, solubility tables, soluhility curves, and a glossary. The Stndy Guide was useful, hut I found it beneficial to modify the worksheets so that students would do those narts of the program that I intended for them t o d a Also supersaturation u,as the concept m,ith which my students had themast difficulty,andyet this concept was not mentioned in the back. ground material nor defined in the glossary. The purpose of a laboratory simulation computer program is to enable students to perform procedures that they ordinarily would not be able to do. Some orocedures are too dangerous. Others mkr roo much timeor thechemicalsand equipment art too expensive. The major criticism that I have of Solt~bilir)is that it simulates lahoratory procedures that are relatively easy for the students to perform in thr laboratory. The miscihility port of theexperiment, fr9resamole, is oerformed so easd\, in real life. that I wonder why anyone wouid want to use that portion of the program. As for the soluhilities of solids in liquids, the pressing of a computer key to add another pellet of solid became boring after a while. And when copper sulfate was used, I was disappointed that the color of the solution did not turn hlue. In the program's favor, these sections would save time and the exoense of the
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chemicals. Perhaps a teacher would wish for their students I,, do one solubility erperiment in the laboratory, and then get some experience with some other chemicals via the computer program. In fact the author of the program does recommend that students perform actual soluhility experiments and be familiar with solubility terminology before using the program. Having had some embarrassing experiments with failed demonstrations of supersaturation, I might recommend that the snpersaturation segment of the program be used as a clase. demonstration. I do not recommend it for student use because of two major problems in the interpretation of the directions. If a student adds enough solute to saturate the solution, this part of the program will not work. The program seems to revert back to the first simulation where solubility curves were being generated. Another problem arises when the student is asked to lower the temperature. If the student chooses to lower the temperature by more than 10 degrees, again the program will not work. The difficulties in interpreting the directions in this part of the program eould be overcome by a knowledgeable teacher who had the foresight to review the program before using it with his class. But because of these difficulties, I recommend that this supersaturation module be used only as ademonstration. An alternative recommendation is that if students are to use this segment of the program themselves, they be given some extra printed sheets with more specific directions. This is how I had my students use the program. With the clarifying information on the printed sheets. none of my students had difficulty in running the program. The author lists six ohjectives. The Solubility program is designed to help students: 1. Master the terminology used in working with soluhility. 2. Understand basic solute1 solvent relationships. 3. Explain the relationship between temperature and solubility. 4. Define and prepare a supersaturated solution. 5. Draw conclusions from the results of soluhility experiments. 6. Improve data interpretation and graphing skills. I believe that a student could accomplish the first five objectives by using this program. I question, however, whether this program would be the best way to accomplish those objectives. As for the sixth objective, I don't think that the program will enhance a student's graphing skills. I would prefer to see a student make his own graph rather than to watch the computer generate one. I used this program with my General Chemistry I1 students at Columbia Greene Community College. The program was available in the Learning Center and students were responsible for running the program on their o m time and filling out the printed sheets that I distributed to them. Students were required to do one of three computer programs, of which E.M.E. Solubility was one. The other choices were Project Seraphim Lake Study and Project Seraphim BCTC Investigation. They eould also elect to do a second or third program for extra credit. Nine of 20 students elected to do the Solubility program. They were required to collect and analyze data on one known solid and one unknown solid, run the supersaturation demonstration on one known solid, and do the simulation miscibil-
ity test on all four liquids. The average time that it took the students to do this was one hour. I was surprised to find out that the students reported no difficulty in running the nromam. I reallv exoected them to have o r o b n s w i t h thk su&rsaturation seement. u I do helieve that rheonly reason they did not have problems was due to the rlarifymg mformation that I supplied to them with the printed materials. No knowledge of computers seems to be necessary in order to run this program. Some of my students had never used a computer before, but appreciated this experience as their first exposure. With the helpof the orinted sheets that I suoolied to them. the students did not need arsistanee to run the pngram or to understand the dtreetiona. I dosuggest that the program be modified to have just one menu to access all four modules. As written, the students need to make three different selections in order to get to either the solubility of a known suhstance segment or the supersaturation segment. One menu and one key press should he sufficient to access any of the segments. The students were asked whether they found the program useful. Eight of the nine students answered affirmatively. One student appreciated the fact that it covered material similar to that which we were discussing in class. Another liked the fact that it was much ouicker to do the exoeriments by computer than hy traditronal lahoratory procedures. A t h ~ r dstudent enpyed finding t yan unknown substance Oththe ~ d e n t ~of ers commented that the program clearly showed them how to find the solubility of a substance and that it cleared up for them the distinction between solute and solvent. The student who didn't find the program useful stated that she did not learn anvthine new from the program, hut that sheenjoyed usmg it. Thestudents uere asked what thpy had learned from [he program. T u o students mentioned miscibility and another mentioned the generalization that solubility of a solid increases with increasing .tempera. ture. Favorable comments from the students included the following: "It helped me in the understanding of solubility." "The computer is much faster than the normal experiment." "I enjoyed the part where I had to figure out the identity of the unknown." "The supersaturation segment was interesting." Negative comments from the students included the following: "Trying to determine which mixtures were miscible in each other was difficult because the graphics were not clear." "The adding of the solute was slow and monotonous. I t took too long." Overall, I do not recommend this program for college level General Chemistry. I t may be more appropriate in a chemistry eourse for nonscience majors or in high school chemistry. The material covered in the program is too small a part and too simple a part of the overall general chemistry curriculum. I would cover the material in less than 15 minutes of a 45-hour course. Also the laboratory experiments are too easy for the student to complete in the actual lahoratory, and I believe that the laboratory experience would be more valuable than the computer simulation. As mentioned earlier, the
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supersaturation demonstration may be useful on the college level, hut the directions need to be written more clearly. J e a n n e M. Gizara Columbia Greene Communltf College Box 1000 Hudson, NY 12534
General ChemMry, Third Edltlon Kenneth W. Whinen. Kenneth D. Galley, and Raymond E. Davis. Saunders College PublisningCompany:New Vork. NY. 1988. xxxii 884 pp. Figs. and tables. 20.8 X 26
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This is a beautifully printed book. I t abounds with multicolored photographs, illustrations, and reoroductions. The mint is clear, generally spaced, and highly iegihle. The paper 13 pleasantly glossy. Taken togprher, these factors make for a wry read. able hook. One of the features of this book, as has been the case in previous editions, is the abundance of exercises to be found at the end of the chapter. The users will encounter little trouble in making homework assignments. The text does a thorough joh of solving an adequate number of sample problems. The authors have seriously atwmpted to present up-to-date materials. Thus, recent developments in such areas as supercanducting ceramic materials and tunneling microscopy have been included. In this vein, the list of elements includes those having atomic numbers 10P107, which have no stahle nuclides. The organization of the h w k is traditional. The usual introductory chapter is fallowed by several chapters on stoichiometry and then structure and bonding. The chapter entitled "Molecular Structure and Covalent Bonding Theories" devotes considerable coverage to the VSEPR theory and perhaps leaves the student with the feeling that it has unusual importance. Chapters 15-21, which cover 204 pages, introduce the student to physical chemistry. All basic physicochemical subjects are adequately covered. Each of these chapters solves a representative number of numerical problems and includes an extensive number of exercises. The last 10 chapters can be classified as "descriptive chemistry". The first of these deals with metallurgy and includes a very brief description of zone refining. Chapter 23 covers the nontransition metals. The halogens and the noble gases are covered in the same chapter. Because of this reviewer's interest in arsenic chemistry, he must object to the statement on page 726, viz., "All ar. ." Insenic compounds are poisonous deed, arsenic compounds are, relatively speaking, not very toxic and arsenocholine and arsenobetaine are really quite innocuous. I t serves little to perpetuate such myths. Transition metal chemistry is the subject of chapters 28 and 29 which cover 47 pages. The chapter on nuclear chemistry includes the important and honest statement, fusion ass practical energy source lies far in ~~
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the future at best." Some of us still remember the 19503s,when we were told that a lump of uranium, the size of a baseball, would furnish abundant, cheap and clean energy almost forever. The final two chapters are concerned with organic chemistry. The approach is quite conventional. The first of these chapters is devoted entirely to the hydrocarbons while the second is concerned with the chemistry of functional groups. The volume reflects the philosophy of most current general chemistry texts in that physical chemistry and numerical problem solving receive the greatest emphasis. Nevertheless, the text is highly recommended. The physical appearance and format are first class, the authors write well and the instructor is assisted by a wide choice of questions and problems for thestudent. The text will serve to provide a solid and up-todate foundation for more advanced chemical training. Raloh A. Zinoaro " Texas A 8 M University College Station. TX 77843 ~
Fundamentals ol Chemislry: General, Organic, a n d Biological Joseph D. Deleo. Scott. Foreman and Company: Glenview. IL. 1988. 793 pp. Figs. and tables. 20.5 X 26 cm. This text is a new entry into the very competitive market of chemistry for the allied health sciences. The standard course for these students includes elements of inarganic ("general"), organic, and biochemistry. The author does admirably well on the latter two areas but slips badly in the first area. Let us address first the good features of this book. The presentation makes frequent use of excellent examples from the areas of medicine, health, and biology to relate the concepts to the students' future careers. These vignettes add a great deal of interest to the textual material. The use of frequent illustrations, margin notes, chapter summaries, and lists of key terms and concepts should enhance the learning process. The concise treatments of organic and biochemistry occupy approximately 58% of the 793 papers and are organized along the standard formats of funetional groups and classes of compounds. The last three chapters on metabolism are especially well done. The quantitative sections include the usual treatments of stoichiometry, equilibria, kinetics, etc. The oxidation-reduction treatment is probably the weakest of these. The author is weak in the realm of descriptive inorganic chemistry. I t is probably desirable that the author was parsimonious as this reviewer has serious objections to some glaring errors. We find an page 119 Hg+ as the ionic species for mercury(I), but curiously Hg202 appears on p. 153. This axide is not well characterized and should he omitted. In the area of nitrogen chemistry,
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Volume 66
(Continued an page A46) Number 1
January 1989
A45
