might seem like a daunting task. Additionally, your lab might
have specific protocols or use special accessories that are not in
the manual. In any case, if it’s your first time using a particular
piece of equipment, ask to spend some time with experienced
colleagues or supervisors to learn how to use it properly.
Begin by running several standards tests or controls that can
easily be referenced. Not only will this help you become familiar
with the instrument, it will also calibrate the instrument for your
experiment. For instance, if it’s your first time using a mass spectrometer, start by learning how to collect the mass of a known
compound and compare it to its standard reference value. While
this does require a significant investment of time, it is important
to remember that during this process, you are acquiring skills
that will be useful with future experiments and will make you a
more well-rounded scientist.
As you become comfortable with the instrument, begin run-
ning your own experimental samples. In order to allocate the right
amount of time for an experiment, roughly estimate how long
it takes to do the experiment, multiply by the number of trials,
and then set aside that amount of time. Something will almost
certainly go wrong the first time through. As you proceed, go
over in your mind the way things are supposed to work, look at
the settings to make sure they are correct, and check the instru-
ment signals such as oil levels, vacuum, pumps, and so forth. Most
importantly, ensure that you are actually recording the data. Many
times students will run their samples through but forget to click
“record” or update their lab notebooks. Document the settings and
readings you obtain, no matter how trivial they might seem. Small
variations can mean the difference between success and failure in
an experiment. Stay focused on your experiment. This is not the
time to multitask by checking e-mail, Facebook, or anything else
until you are absolutely sure everything is routine.
As data are being collected, you should decide whether the
results are those you anticipated. Is your hypothesis reasonable?
Is the data signal what you expected? If not, is the experiment
running correctly? If you decide that the instrument is at fault,
check the standards — a series of blank samples that are identical
to yours but missing the reagent you are analyzing. In addition,
Daniel Robie, assistant professor of chemistry at York College,
CUNY, recommends going over a simple checklist. Robie has dealt
with instrumental problems while designing laser-based research
experiments to study chemical reactions. He recommends checking the following:
• Check for faulty power switches, blown fuses or circuit breakers,
weak batteries, and unplugged cables.
• Are the values for instrument parameters correct?
• Are reagents fresh? At the right grade of purity?
• Have your compounds hydrolyzed? Water in the air or workspace
can interfere with the results.
• Consider possible temperature or vacuum effects.
• Finally ask for assistance.
• Reboot computers, and restart the instrument if possible.
February/March 2015 www.acs.org/undergrad • inChemistry