Creating QuickTime Movies to Demonstrate Lab 
Experiments


at the


University of Wisconsin-Madison


prepared for


The Institute on Learning Technology


part of the


 


Spring 2001

This quicklook also is available from the
Learning Through Technology web site,
http://www.wcer.wisc.edu/nise/ilt/


Creating QuickTime Movies to Demonstrate Lab Experiments


Art Ellis
Professor of Chemistry 
University of Wisconsin-Madison
ellis@chem.wisc.edu





George Lisensky
Professor of Chemistry
Beloit College
lisensky@beloit.edu





Jonathan Breitzer 
Post doctoral Associate
Materials Research Science and Engineering Center
breitzer@chem.wisc.edu





Why use technology?
The use of QuickTime web-accessible videos helped us to demonstrate visually to our students 
(and other instructors) how to set up a particularly difficult-to-explain lab experiment on 
ferrofluids.  The methodology can readily be extended to other labs.  

Originally developed by NASA, a ferrofluid consists of magnetic nanoparticles suspended in a 
liquid. Ferrofluids have a very captivating property: when you bring a magnet close to them, you 
see spikes created as the particles attempt to order themselves in the magnetic field, as shown 
in Figure 1 below.  

Figure 1: A ferrofluid responding to a cow magnet
 

"Ferrofluid synthesis and properties" is an engaging, thought-provoking lab experiment. 
Students start with two colored solutions that show no visible response to a magnet whatsoever. 
They mix them together to cause a chemical reaction, apply a few lab procedures, and then, 
voila, they have this remarkable black liquid that responds to a magnet.  

However, some students became frustrated in trying to follow the text-only descriptions and too 
often did not succeed in producing the ferrofluid.  In addition, some of our colleagues had 
difficulty doing the lab based on an article we wrote about it in the Journal of Chemical 
Education. 

To address these problems, we filmed all the steps of the lab, converted them to QuickTime 
movies, added written explanations, and made these web-accessible.  This conversion into 
video reduced several paragraphs of dense text to a sequence of easy-to-follow steps.  
Students really liked the videos describing the process; the videos helped them to understand 
each step of the lab and to know whether they were on the right track in creating the ferrofluid.  
The videos also made a difference in their success in the lab: we could tell which students had 
watched the videos by the ease with which they did the experiment. 

In addition to the ferrofluids lab, we have created movies to demonstrate other lab experiments, 
such as the preparation of colloidal gold particles.  These are available at the Materials 
Research Science and Engineering Center on Nanostructured Materials and Interfaces 
(MRSEC) website.  The MRSEC is generously supported by the National Science Foundation 
(NSF), where Art is the director of the education and outreach component.  These lab 
experiments and the movies have been created for the purpose of bringing the excitement and 
results of research on nanoscale science and technology to students, teachers and the general 
public. 


The strategy
The process
Our process was to dissect the lab into a sequence of steps, with written directions.  George 
and Jonathan filmed the stages of the experiments and George formatted them for the web. 

For example, the steps that have been filmed for the ferrofluid lab are:

Step 1:	Visually checking that the solutions are properly prepared.  
Step 2:	Mixing and stirring the iron solutions.
Step 3: 	Precipitating magnetite by slowly adding an ammonium hydroxide solution 
using a burette.
Step 4:	Separating the magnetic stir bar from the product with minimal loss of 
material. This process is hard to describe in words.   
Steps 5-7:	Decanting and washing the ferrofluid. Manipulations involving magnets are 
not common procedures in chemistry laboratories.
Step 8:	Adding and mixing the surfactant.
Step 9:	Demonstrating the response of the ferrofluid to a magnet, an indication that 
the preparation was successful.  

Using QuickTime
We chose to use QuickTime rather than alternative video players for several reasons. First, 
QuickTime is popular and easily-accessible: it comes as a standard plug-in with many browsers. 

Second, QuickTime can be stopped in the middle of a running movie and advanced frame by 
frame using the arrow keys.  This transforms a "passive" video into an interactive piece of 
software, enabling students to make more detailed observations of the lab.  For example, we 
have developed another module on amorphous metals in which we do a comparison of an 
amorphous metal (i.e., one that has tightly-packed atoms but no pattern of packing) to a typical 
metal like steel (i.e., one that is crystalline with a patterned packing arrangement).  The video 
demonstrates that a bouncing steel ball loses comparatively little energy to the amorphous 
metal relative to the crystalline metal.  Students can use the feature of stopping the video to 
measure the height of the "bouncing" ball on each bounce to make quantitative comparisons as 
a function of time for the two surfaces.

Lessons learned along the way
We learned a few things through the process of creating these videos.  It is trickier than it looks 
to decrease the file size while maintaining high quality.  Some suggestions:
_ Spend time obtaining a good quality movie, because better quality images compress to a 
smaller size. Use a digital video camera, a tripod, and a plain background.  Pay attention 
to the lighting so that it really highlights the lab.
_ Use a good compression algorithm.  A minute-long movie can be 100 megabytes to a 
gigabyte of data and it will need to be reduced to 1-2 megabytes.  We use Sorenson 
compression software and two-pass encoding that is used by graphics professionals. 
_ We have decided that a reasonable video size is 320 x 240 pixels and a reasonable file 
size is 1-2 megabytes.  This is already a large file -- especially for modem users -- and 
we do not plan to create larger files or movies sizes in the near future because of the 
potentially long download time.


Project Support
Funding has come through the NSF-funded Materials Research Science and Engineering 
Center on Nanostructured Materials and Interfaces (MRSEC).  The MRSEC is an 
interdisciplinary research center based at the University of Wisconsin-Madison that brings 
dozens of researchers together to conduct cutting-edge research related to nanoscale science 
and technology.  As part of the MRSECÕs education component, we try to find effective ways to 
communicate to different audiences, including students and the public, what the nanoworld is all 
about, why it is exciting, and why it will have technological and economic impact.

The MRSEC website has many instructional resources that can be drawn upon.  In addition to 
the ferrofluids lab, we have many other experiments that highlight scientific and engineering 
principles.  All of the labs and demonstrations are connected to papers we and others have 
published.  The website also has information about where to purchase the materials needed to 
do the experiments. 


The learning technology
The QuickTime videos that describe the lab setups and experiments involving nanotechnology 
are available at the MRSEC website.  

We started this work before the network connections were fast enough to run these pictures.  
Originally, we put movies like these along with other materials (animations, text) on solid-state 
chemistry on a compact disc and distributed them through the Journal of Chemical Education. 


The courses
All three of us use the ferrofluid lab in our general chemistry courses.  We have done this for 
several years and have found it successful.  One of the things we both try to do in our 
introductory courses is make chemistry a lot more exciting, by bringing in a connections to high-
tech materials and devices.  Ferrofluids are a good example: we make clear to students that 
ferrofluids are used in all kinds of high-tech applications, including disk drives and loudspeakers, 
and they may have medical applications in the area of drug delivery. 

Art's class
I teach a 600-student general chemistry course for science and engineering majors.  Many of 
these students do not plan to become chemistry majors. Jonathan has helped me with the labs 
to ensure that they ran smoothly.  This was the first year (Fall, 2000) that I have used the 
movies describing the lab process, and I found that the lab required considerably less oversight.  

In addition to the QuickTime movies, I use WebCT, which is a type of class management 
software that the UW-Madison has purchased. I like WebCT because it organizes the course 
information, including syllabus, lecture notes, announcements and grades, in one place.  I have 
used WebCT to give pre-lab quizzes, in which I ask students questions about the movie to 
encourage them to watch it prior to the lab.  A graduate student teaching assistant, Cindy 
Widstrand, has helped me to work effectively with WebCT. 

George's class
We have much smaller classes at Beloit and have several instructors, who will teach different 
sections of the same course.  During the semester prior to our filming of the ferrofluid lab, only a 
few students succeeded in the synthesis. I persuaded the other instructors to try again with the 
videos as a pre-lab assignment.  This time, almost all the students were successful in creating 
the ferrorfluid. I do not believe this means that all the students carefully studied the video before 
lab, but enough students did so that they could serve as models for others.

Our students are accustomed to accessing web sites and video as part of the course because 
we use computer-based Wiley ChemConnections modules in this class.  These modules center 
around a particular science-based issue, like the ozone layer or water quality, and were created 
by the ChemLinks chemistry consortium here at Beloit Colleges and published by John Wiley & 
Sons.   


Student responses
We have found the pre-lab movies to be helpful to many of our students. In fact, in Art's class, 
61% of the students who responded to his survey (N=300) found the movies to be useful in their 
execution of the lab.  A few commented on technical difficulties (e.g., unable to get the movie to 
run), but most students appeared to enjoy the pre-lab movie and found it helpful.

That [the pre-lab] helped out a lot. I knew exactly what I had to do before the lab. It cleared 
up all the questions I had about the experiment prior to watching the movie.  You should do 
this for all the labs!!!

It helped our group a lot because then we had a better idea of what to do. Sometimes just 
reading it doesn't give a good enough picture of the lab procedure. 

I always learn better when I see something happen first. Also, it cleared up some things in 
the lab that were described, but I didn't quite completely grasp. At the very least, no one was 
at a disadvantage of not knowing how the ferrofluid was supposed to work if theirs didn't turn 
out in lab. 

If you have any questions about the videos or the labs, you can contact Art Ellis at 
ellis@chem.wisc.edu or George Lisensky at lisensky@beloit.edu.


LINKS
Materials Research Science and Engineering Center Education and Outreach: 
http://www.mrsec.wisc.edu/edetc
Nanoworld Cineplex:
http://www.mrsec.wisc.edu/EDETC/cineplex/index.html
Materials Research Science and Engineering Center:
http://www.mrsec.wisc.edu/
Art Ellis' home page:
http://www.chem.wisc.edu/~ellis
George Lisensky's home page:
http://www.beloit.edu/~chem/lisensky/
WebCT:
http://www.webct.com/
ChemLinks:
http://chemlinks.beloit.edu/
Download QuickTime 5:
http://www.apple.com/quicktime/download/