NAME

       chemeq - Chemical Equation Parser and Renderer

SYNOPSIS

       chemeq [-M] [-m] [-l] [-c] [-w] [-C] [-e] [-s] [-n] [-W]

       chemeq [-h] [-v]

DESCRIPTION

       chemeq is a chemical equation analyzer. It is a fast lexical and syntaxic analyser which
       helps to find out chemical informations embedded in source chemical equations. Data can be
       output in various sophisticated formats, depending on options. 'chemeq' defaults to
       'chemeq -mlcwCn'.

OPTIONS

       -M
           Outputs al list of space separated molecular weights.

       -m
           Outputs a minimal output. It allows chemeq to be idempotent, i.e. the command 'chemeq
           | chemeq' is equivalent to 'chemeq'.

       -l
           Outputs a LaTeX string representing the chemical equation.

       -c
           Outputs a message giving informations about the Conservation of elements and charges
           in the equation. 'OK' means that both elements and electric charges are balanced.

       -w
           Outputs the LaTeX string representing the Gulder-Waage equation related to the input
           chemical equation, or the Nernst equation, if the input equation is a redox
           semi-equation.

       -C
           Outputs a detailed Count of the molecules and atoms contained in each member of the
           chemical equation. For example for the equation "H2_g + 1/2 O2_g --> H2O" it outputs:
           "H2_g|H:1*2, 1/2 O2_g|O:1/2*2; H2O|H:1*2 O:1*1"

       -e
           Outputs a detailed count of the Electrical charges.

       -s
           Outputs a list of the chemical Species.

       -n
           Outputs a Normalized string accounting for the input equation. Two chemical equations
           having the same normalized string are chemically equivalent, even if the molecules are
           scrambled around and the coefficient are not equal but proportionnal.

       -W
           Changes the behavior of the renderer for some versions of Wims : works around a bug
           whith the macro \rightarrow.

       -h
           Displays Help.

       -v
           Displays the Version number

ENVIRONMENT

       chemeq_input, w_chemeq_input
           if set, this variables's value overrides the standard input. If this variable is not
           set, the variable w_chemeq_input is taken in account (useful for the WIMS server).
           See above (useful for the WIMS server).

       chemeq_option
           if set, this variable's value overrides the options.If this variable is not set, the
           variable w_chemeq_option is taken in account (useful for the WIMS server).

       w_chemeq_option
           See above (useful for the WIMS server).

EXAMPLES

       echo "1/2 Cu^2+ + OH- -> 1/2Cu(OH)2s" | chemeq
           will display informations about the reaction of hydroxyde and Cu II ions.

       echo "MnO4^- + 8H3O^+ + 5e- --> Mn^2+ + 12 H2O" | chemeq
           will display informations about the reaction of reduction of permanganate ions in an
           acid environment.

       echo "MnO4^- + 8H3O^+ + 5e- --> Mn^2+ + 12 H2O" | chemeq -w
           will display the LaTeX format for the Nernst law related to the reduction of
           permanganate ions in an acid environment.

       echo "MnO4^- + 8H3O^+ + 5e- --> Mn^2+ + 8 H2O" | chemeq -c
           will highlight the lack of conservation of elements H and O (water molecules are not
           well balanced).

NOTES

       syntax of ions
           allthough in some cases, shorter expressions are sucessfully parsed, it is safer to
           consider that an "up arrow" (^) must be put before the charge symbols of an ion.
           Examples : H3O^+, Fe(CN)6^4-, OH^-

       Composing chemical equations
           Two operators are defined, # as an additive oprator and ~ (tilde) as a substractive
           operator: they allow to compose several chemical equations

            echo "MnO4^- + 8H3O^+ + 5e- --> Mn^2+ + 8 H2O ~ 5Fe^3+ + 5e- -> 5Fe^2+" | chemeq

           will display the pure redox equation from the first equation, minus the second one.
           Electrons are simplified. So it will be equivalent to:

            echo "MnO4^- + 8H3O^+ + 5Fe^2+--> Mn^2+ + 8 H2O + 5Fe^3+" | chemeq which is their
           combination.

       Mutiplying a chemical equation by one coefficient
           The operator * permits to multiply a whole equation by one coefficient which may be a
           fraction. Here is an example:

            echo "5 * Fe^3+ + e- -> Fe^2+" | chemeq

           will be equivalent to

            echo "5Fe^3+ + 5e- -> 5Fe^2+" | chemeq

       Combining chemical equations, with coefficients
           The two previous techniques can be used at the same time, which enables you to make
           more comlicated combinations, like this one:

            echo "Fe^3+ + e^- -> Fe^2+ (0.77 V) # Fe^2+ + 6CN^- -> Fe(CN)6^4- (Kfa=1e24) ~ Fe^3+
           + 6CN^- -> Fe(CN)6^3- (Kfb=1e31)" | chemeq

           which will work as expected, and yeld a good value for the stan‐ dard potential of the
           redox couple of hexacyanoferrate II and III ions.

KNOWN BUGS

       When not specified, chemical entities coming from the standard input are believed to be in
       aqueous solutions. Water is considered by default as the main solvent. Only one liquid
       (aqueous) phase is currently taken in account. All solid chemical entities are considered
       as parts of separated phases. Suffixes _s, _g and _aq can be used to enforce the type of
       some chemical entities. There may be problemes when you write a standard potential with no
       decimal dot. For example, the entry Mn^2+ + 2e^- -> Mn_s (-1 V) would trigger an error.
       Then write Mn^2+ + 2e^- -> Mn_s (-1.0 V) or the more accurate value Mn^2+ + 2e^- -> Mn_s
       (-1.18 V) and there will be no error.

AUTHOR

       Georges Khaznadar <georgesk@debian.org>
           Wrote this manpage.

COPYRIGHT

       Copyright © 2000-2013 Georges Khaznadar

       Redistribution and use of this manpage in source and binary forms, with or without
       modification, are permitted under the terms of the GNU General Public Licenses, version 2

       THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
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       PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
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       LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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