Molecular Weight Calculator 1.07 Copyright © 1999-2008 Henning Umland
Chemical Formula:
Molecular Weight:
Reciprocal Weight:

Instructions for use:

Enter a chemical formula in the way it is usually written, as shown in the following examples:
Fe3[Fe(CN)6]2 or Fe3(Fe(CN)6)2

Simplified structure formulas are also allowed:
H3C-(CH2)7-CH=CH-(CH2)7-COOH, etc.

Symbols can be separated by blanks:
Na2 S O4 or Na 2 S O 4 is processed in the same way as Na2SO4.

Formulas containing a dot indicating a hydrate or other adduct, like CaSO4 · 1/2H2O, have
to be entered using the format CaSO4(H2O)1/2, CaSO4(H2O)0.5, or CaSO4(H2O).5
since the program regards any dot as a decimal point.

Do not enter numbers composed of an integer and a fraction, like 1 1/2 (will be read as 11/2).
Use 3/2 or 1.5 instead.


This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the license or any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License ( for more details.

Henning Umland    N 53° 20' 34''   E 9° 52' 00''

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