Record all of your observations in your lab notebooks. Each of you
should have you own drawings of each spectrum.

\textbf{In all of your drawings: try to make clear the distinction
between sharp and fuzzy lines, bright and faint lines, and regions
where the continuum is bright or faint. Also make sure to indicate
whether you are using ink on the paper to represent light or the
absence of light.}

\section{Spectra of light bulbs}

\subsection*{Materials} spectroscope

\subsection*{Instructions}

Observe the light sources listed below through your
spectroscope. Remember that you need a fair amount of light to be able
to see a spectrum. In order to see the spectrum you need to line the
light source up with the slit. The spectrum will then appear to one
side of the slit. It may take some practice to get the hang of lining
the light source up in the slit.

Also try to make sure your spectrum isn't contaminated by some other
light source.

\textbf{For each object you observe:}
\begin{itemize}
\item Describe it.
\item Write down where you found it.
\item Draw its visible spectrum.
\item Classify its spectrum as emissions line, absorption line,
  blackbody, or other (explain).
\item Explain why the object has that type of spectrum.
\end{itemize}

\noindent Light sources:
\begin{enumerate}
\item As many different kinds of indoor lighting as you can find (at
  least three). Make sure one is an incandescent bulb.
\item As many kinds of outdoor lighting as you can find (at least
  two). You can look through the windows. Note lights that appear to
  have different colors, as these will show different spectra.
\item Something emitting light that is not listed above. Think about
  things that might emit light, and feel free to scout around the
  building for candidates.
\end{enumerate}

\section{Safety note on gas tubes}

Power sources should be turned off and unplugged before gas discharge
tubes are touched. The gas tubes can get quite hot after a while, so
exercise caution and ask a TA to help you when you want to change the
tubes.

\section{Spectroscopy of known gasses}

\subsection*{Materials} spectroscope, labeled gas discharge tubes,
printout of gas spectra

\subsection*{Instructions}

I have set up two power sources at a table with several different
gasses in labeled discharge tubes. It may take some practice to get
the hang of lining the spectroscope slit up with the tube. 

\textbf{For each gas:}
\begin{itemize}
\item record the name
\item draw its visible spectrum
\item compare its spectrum to the spectrum in the printout and note
  any differences
\end{itemize}

\section{Spectroscopy of unknown gasses}

\subsection*{Materials} spectroscope, unidentified gas discharge tubes,
printout of gas spectra

\subsection*{Instructions}

I have set up two power sources at a table with several different
gasses in discharge tubes labeled only with a letter. 

\textbf{For each unidentified gas:}
\begin{itemize}
\item record the label
\item draw its visible spectrum
\item identify the gas by comparing its spectrum to the spectra in the
  printout, or to the spectra you have observed in the labeled gas tubes
\end{itemize}

