Chemistry


Allegheny College
Mastering chemistry concepts and scholarly research

Reproduced with permission from NeXT Computer, Inc.
A Reference Guide to NeXT in Higher Education, Fall 1992
ยช 1992 NeXT Computer, Inc


In chemistry classes at Allegheny College, NeXT computers are as essential as the periodic table of elements, thanks to Assistant Professor Brian Reid and his colleagues Nancy Lowmaster and Sally Hair who have created a plethora of NeXT-based applications for both upper- and lower-division courses.

"I appreciate the speed, development environment, and graphic capabilities on NeXT," says Reid. "I had created applications on the Macintosh and IBM platforms prior to working on NeXT machines. But what I developed on those platforms seems primitive to what I've been able to create with NeXTSTEP. NeXT's speedy calculations, smooth animation, multitasking, and Interface Builder are all great.

"We're using the NeXT applications to address some of the more difficult concepts in our curriculum," continues Reid. "Many of the applications we've been able to create really help students see things graphically. These are concepts that are often difficult to illustrate on a blackboard,"

For introductory courses, Reid and Lowmaster developed a NameThatCompound application that allows students to quiz themselves on the names and formulas of inorganic compounds. The applications tracks the students' responses and gives a score at the end of each session. Another application, VSEPR, lets students determine molecular shapes. Students draw electron-dot structures and select the correct molecular geometry from possible structures displayed on the screen.

"These applications have worked quite well," says Reid. "In fact, the classes that have used NameThatCompound have mastered the nomenclature much better and faster than previous classes."

He has created a periodic table application in which students can click on a particular element and read information about that element, including when it was discovered and its uses.

Reid also has developed applications that let students prepare for labs. For example, students are asked to test the different reactions caused by mixing various chemicals, and the computer provides a response about that reaction. Once students determine the appropriate reactions for an experiment , they perform them in the laboratory.

"The computer allows the students to experiment with all the possible reactions among a set of reagents. We can't try them all in a lab setting, mostly because of the time factor," says Reid. "Students have reacted very positively to being able to figure things out on the NeXT before they do their labs."

When introductory classes study hydrolysis reaction rates in the laboratory, they analyze their data with an application Reid devised. In the application, students record their data and use different graphical models to determine the reaction rate law.

Reid and Hair have created several applications for upper-division laboratories. RealGases allows students to change the parameters of a real or ideal gas with sliders and then determine the effect on pressure-volume isotherms. Using Virial, students use Virial plot second virial coefficient data obtained in the lab and compare them with computer-calculated values based on a molecular model. PhaseI plots experimental data from a binary liquid-solid system and lets students compare their experimental phase diagram to a theoretical calculation. ConjugatedDyes is a tutorial and exercise program for investigating the energy levels of brightly colored molecules. IR shows the molecular vibrations responsible for the infrared spectra of molecules, including carbon monoxide, hydrogen chloride, carbon dioxide, methanol, and sulfur dioxide. DyeLaser animates the molecular level processes that occur in a dye laser.

Another custom application, Diatomic, animates the motion of molecules with two atoms. Students can observe the effects of adding varying amounts of energy for vibration and rotation as well as plot molecular energy levels and their relative populations. "The Diatomic application has allowed us to perform an exercise we've never been able to do before," says Reid. "With Diatomic students can visualize the motions of molecules and interact with them."

He continues, "Interface Builder and the Application Kit have been very helpful in developing all these applications. "We are able to design much nicer interfaces more quickly than we could with other platforms. I originally wrote the Diatomic application for the IBM and Mac, but students like the interface on the NeXT version even better."

Reid says he also relies on the NeXT network for distributing solutions to homework problems, new assignments, and lab procedures. "The network is useful because it saves me from distributing paper versions or posting homework solutions outside my office," says Reid. "With this method, students have better access to solutions and course information."

The NeXT machine's networking and multitasking capabilities also come in handy during the junior seminar for chemistry majors that Reid teaches. For the course, students are required to conduct literature searches by accessing the chemical abstracts database via the Internet.

"Students use WordPerfect or WriteNow to write out their search strategy. Then they're able to conduct the search in a terminal window while viewing their search strategy in another window. They can keep track of the information they've obtained and copy and paste the search results into the WriteNow or WordPerfect file. Because of its multitasking capability, NeXT provides an excellent environment for conducting an on-line search."

For more information, please contact:

Brian Reid
Assistant Professor of Chemistry
Allegheny College
Meadville, PA 16335
(814) 332-5329
breid@alleg.edu