Chemistry::Mol seems to do all that, including parse the formula.

$ perl -MChemistry::File::Formula -e'my $mol = Chemistry::Mol->parse("
+Pb(CO3)2",format=>"formula");print $mol->mass,$/'
327.2178
$

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After Compline,
Zaxo

In reply to Re: Regular Expresions and atomic weights by Zaxo
in thread Regular Expressions and atomic weights by hokie

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