Molecular Weight Calculator (16-bit) (by Matthew Monroe) calculatess the molecular weight and percent composition of up to seven compounds simultaneously. It can recognize up to 150 user-defined abbreviations and all isotopes. It can handle embedded parentheses, multiple hydrates, and has the unique ability to weight certain parts of a compound. An advanced feature of the program is its ability to solve for "x&quot\; in a compound based on user-specifed percent composition data ( for example C6H6-[xH2O]).Other features include a Mole/Mass Converter and a Formula Finder, plus standard deviations of results, automatic case conversion, and optional recognition of the amino acids.It includes extensive error checking to verify that formulas entered are valid, and optionally displays caution statements for formulas with unusual element combinations. All features can be set at the command line or saved during program operation. It also includes a built-in mathematical calculator