Osmosis and diffusion (Chandler, James) - Journal of Chemical

Jan 1, 1988 - Two comprehensive reviews of a software program that illustrates experimental simulation covering concepts of diffusion, osmosis, random...
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Osmosis a n d Diffusion James Chandler. Educational Materials and Equipment company. P.O. Box 17. Pelham, NY 10803 Hardware: Apple i I family Componentm 1 program disk. 1 backup disk. teacher's guide, set of student lab booklets. Level and Sublect: High school and college general chemistry, simulation of osmosis. Cost: $45, also available for TRS-80 model 3 and 4: $47.00

Features and Intent The program is a flexible combination of CAI and experimental simulation covering the concepts of diffusion, osmosis, random motion, and the properties of cell plasma membranes. Students will be able to learn terminology, test the effects of manipulating variables, and practice evaluating hypotheses in light ofthe experimental results. The program enables students to gather raw data and then directs them to record and eraoh the data in an accomnanvine Student ~ a i Booklet. l Conclurions based on these experimenuare then required. There is also s self-checking qu:z available at the end uf the program. The level of this program is suitable for intrqductory chemistry or biology dssses a t both the high school and college levels. I t would be helpful for students to have performed or at least observed actual exoerimenta on drffwon and osmosrv before startmg to work wrth the program.

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is an accomnanvine "Studv Guide" which appears to be aimed at the teachers. This gives some helpful background information and suggestions for use. There is just one major source of confusion in running the program. When you first load it, the followingfour options appear on the screen: 1. Introduction 2. Experimental Mode 3. Quiz 4. End Program

Students run the introduction first in order tu become familiar with vocabulary. Then the Student Lab Booklet instructs the user to run the Demonstration program. This direction is confusing, because no Demonstration program appears in the menu. Choice 2, the Experimental Mode, should he selected. Then a new menu appears, which gives the following choices. a. -Emlanation -~ h. Set Up Your Own Experiment If the first choice, Explanation, is selected, the demonstration program is activated. Once this hurdle was passed, students had no difficulty in using the program successfully. The prompts are clear and the only major complaint logged by the students was the time factor. In many of the experiments, the total time required was too great ta avoid impatience.

the concepts of osmosis, diffusion, random motion, and cell membranes. Although this program will he useful in learning the stated subject matter, the real excitement lies in the way in which students will be able to practice critical thinking as applied to experimental design and interpretation. Some teachers may wish to use this program as a means to increase understanding about how ta olan. . . carrv- out.. and interoret an exoeriment. even if the subject matter content dues not fit perfectly within their uourre outlines. Pedagogic Value There are some fairly traditional aporoaches beine used here. includine renews of vocabulary, data gathering, and self-quiz opportunities. The dynamic pans of the program are itsstrength, however. This prugram provides a visual way for students to experience the processes associated with diffusion and osmosis. The new ground hroken hy this program is in its treatment of experimental design. As mentioned above, this feature should be considered as one of themajor reasonsto use this program. I t allows fairly open-ended exploration without the constraints of lab time and costs that would be required to perform the experiments being planned.

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Subject Matter Content

Student Reaction

The content appears to be correct and appropriate for an elementary treatment of

Osmosis and Diffusion was tested principally by students in my general chemistry

Ease of Use

Summary Ratings:

The program disk is accompanied hy a Student Lab Booklet. This provides some structure for the students as well as a place to record data and answer questions. If the student's interactions with the program were part of an assignment to he graded, the lab booklet would certainly help to standardize the format of responses. There also

Ease of Use Subject Maner Content Pedagogic Value Student Reanion

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A e v i e w e d In This Issue Reviewer

Computer Learning Package J a m e s Chandler, Osmosis and Diffusion Roger Shelton, E. M. E. Titration Lab S. N. Demingand S. L. Morgan, Simplex-V: An Interactive Computer Program for Experimental Optimization

Lucy T. Pryde George 6. Powers Philip H. Ogata James P. Deavor

A22

Ward Knockemus Daniel T. Haworth

A25 A25

William D. Schuiz George B. Kauffman

A25 A28

A23 A24

Books Morris Hein, Foundations of College Chemistry

James E. Brady and Gerard E. Humiston, General Chemistry Principles and Structures. Fourth Edition B. Boikess, K. Breslauer, and E. Edelson, Elements of Chemistry W. H. Brock, From Protyle t o Proton: William &out and the Nature of Maner 1785-1985 Titles of Interest Continuing Series

A22

Journal

of Chemical Education

A28 A27

class and hy a few biology students in a n introductory class. Most student reaction t o this program was favorahle. Of the approximately 40 evaluators who completed the entire program, 12% rated it as excellent, 68% as goad, and 12%as average, with only scattered responses of below average or poor. An interesting pattern emerged in the detailed responses of these students. Many of the less experienced computer users were among those who were most impressed with the momam. Thev* tended ta find the use of the program "informative as well as recreational". Mnny commented un the game-like aspects d the early partr of the program. The more experienced users werp leas impressed by the technical details of the p ~ , n a m itself. Although they slaofelt that they toextend their study had learned some of the properties of solutions, they tended to sueeest and f a r re.... that better -erauhies . sponve times would improve the program. Other suggestions were to include dirrussiun uf *tatistical variation and more feed. back from the computer when aquestion in the self-quiz section was missed. Some of the more advanced students who had studied osmosis in other science courses did not feel sufficiently challenged by the subject content, reinforcing the observation that this program will work hest for introductory-level students. Many of the students did not care for the directed format of moving hack and forth from the screen t o a lab booklet. They found that process distracting, although they recognized the usefulness of this booklet. Sugeestions for imorovement here included moditling the program so it offered the option i r f directly entering dntn into the computer and generating the graphsun thecomputer. The best feature of the program for the students was the aspect of experimental design. Even the more sophisticated users had not seen this approach, and they liked i t verv much. Because manv of them did not know much about osmosis, the results were not predictable, and they felt they were conducting a "real experiment". Some of the students worked in groups of two in order t o complete their assignment based on the program. This seemed t o work well; their discussions with each other were directed and h e l ~ f uin l clarifvine the meanine of emerimental results. Thetime snent wi;h the'program varied from 1 . 5 4 hours with :I 3.5 h w r s bring the norm for what they were asked to arcumplish. ~~~~

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Recommendatlons for Improvement The fit hetween the program and the student lah hmklet needs t o be tightened. The option to speed up the .'timed" cycles is essential in the opinion of d l users. Explanation of the assumed allowable limit6 of statistical variation would greatly enhance student understandine. It would benefit some usera u, mrorporate the optlon of be~ngnhlementer data and graph i t uslng the computer itself. An effort could he made t o relate the chosen experiment to real situations. For example, if a large water-soluble molecule were chosen in an experiment, the student could he helped to connect this to some physical reality with the observation that the chosen

molecule is similar t o glucose, followed by a few observations about how this might he important in natural systems. Summary Although the process of osmosis is not usually given too much discussion in general chemistry, it is a very important idea for the majority of our students who use chemistry as a service course for other majors. This program would provide a way to introduce or review osmwis, diffusion, random motion, and the variables that affect membrane transport. The pedagogic strength of this program lies in its unusual approach to designing and interpreting experiments. The law cost ($45) of the program makes this choice of software a good instructional value. Lucy T. Pryde Southwestern College 900OtayLakesRoad Chula Vista, CA 92010

challenged advanced students t o vary the experimental conditions. The ease of use and student reactions convinced me of this. George 0 . Powers Old Town Hlgh School Old Town. ME 04468

E. M. E. Tltratlon Lab Roger Shelion. Educational Materials and Equipment Company. P.O. Box 2805. Danbury. CT 06813. Hardware: Aaale I i famllv components-i d~skand backup. Student Lao Booklets and Study Gu~de Level and Subject: Hngn School Chemistry Cost: $47.00. Summary Ratings: category E m of Use: Sublect Miter Content:

Peda~ogicValue: Student Reaction:

Review II Osmosis and Diffusion covers several different aspects of the use of the computer. In additinn eeneral information. .. to .. nrovidine r ~ . ~~~~" the program user experimentation and testing. 1 found the program tu he usable for my students. I have average or above average students in my chemistry classes. The program could he used whether or not the topic had been previously covered in class. I found t h e material extremely user friendly! Several students, some with and some without computer experience tried this material. Neither group had any difficulties using the program! The documentation was excellent and complete. There was a general guide as well as student lab hwklets. The bwklets provided not only a way of taking notes during the program hut also a data table to complete the experimentation part of the program. Instructions were given on the screen as well as in the booklets. The program can be used with minimal equipment. No additional hardware is needed except the computer, disk drive, and screen. The entire program runs smoothly and easily. The choices shown on the screen are always clear. One convenience is the use of the right and left arrow to go ahead or go hack t o review any screen. This program might he used in several ways: tutorial, self teaching, or remedial. I found the subject matter t o he presented in a clear and straightforward manner. We could not find any errors in the material presented. I did not test the program with students that had not been exuosed t o the mplc hefore. The program was not designed ~ a l l u wthe teacher to modify it. The s t u d e m that used the programs felt that the material was presented well and completely. They found the experiment to be very useful and helpful. Several found the experiment to he the hest part, while othersliked the explanation and quiz better. All mouos thoueht that the ouiz did a e m d l o b i n r o v e r ~ n ~ t h e m a t ~ rAll i d 'thestudents enloyed usmg the computer t o learn. In cuncluaron. I would definitely recommend this program for any teacher who teaches osmosis and diffusion! I t was general enough for any student to use but also ~

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As indicated in the student guide, the E. M. E. Titrotion Lob is an interactive orogram that combines computer-~ssistedInstruction (CAI) with a lab simulation. The major objectives of the program are fourfold. First, the program is designed to help the student master titration procedures. Second, the program will help the student understand certain concepts-molarity, pH, Kw, ion dissociation, E notation, and acid-base neutralization. Third, the program helps the student understand chemical symbols, empirical formulas, metric units, and the use of a buret. Finally, the program will help the student improve on laboratory data collection and computational skills. The Titration Lab program is designed for the average and a h & average first-year chemistry student in a beginning high school chemistry class. Because of the nature of the program, the goals are too far reaching. The student must know the concepts before entering the program. Also, the student must already be familiar with the use of chemical symhols,formulas, metric units, and the basics of titration. The best aspects of the program are the visual collections of data and improvement of comnutatioual skills. Therefore. the urogram i; very good for reviewing ibros br a rerien before nctually undrrlsking n tirration in the lnhornrory. However, thp pragram is a poor suhstitute for an actual titration experiment. The documentation for this program is excellent. The overview includes the nature of each part, what each module includes, and the goals of the general program. Next is aratianale for a simulation of a titration lab. One can concentrate on important concepts without being distracted by experimental details. Finally, there is background information on the general titration procedure and definitions of some general terms (titration, indicator changes, end point and concentration determination). In addition, a student lab booklet is available, even though the program is self contained. The hooklet summarizes part B of the program, the math

Volume 65

(Continued on page A24) Number 1

January 1988

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