iChem, written in Cocoa for Mac OS X exclusively, is a full-featured periodic table and molecular weight calculator. It offers a multitude of features you won't find in many other places. The molecular weight calculator alone is invaluable to chemistry professors, students, and practitioners the world across.
Version 1.3 adds the following:
- Moved registration scheme to the FSS style
- Updated some information on a few elements
- Fixed a small leak in the molecular weight calculator
- Mac OS X 10.1 or later