For your chemistry homework ...
In FC3 there is a character map tool in main menue > accessories - follow your nose. Select the "greek" language and copy the characters over. You can cut and paste from your wordro. OR you can download the standard symbols font from microsoft?
However, if you plan to continue in sciences, take some advice from an old hand... learn to use latex. No kidding no itshay. It is actually designed to handle scientific documents - you can even print full chemical formulae properly formatted as well as mathematical relations. FC3 comes with latex and pdflatex. Good tutorials are available from
http://www.ctan.org (I think).