Raku Chemistry::Stoichiometry

Introduction

Raku package for Stoichiometry procedures and related data. The primary functionalities are:

• Calculation of molecular masses for chemical compound formulas

• Chemical equations balancing

Here are corresponding examples:

use Chemistry::Stoichiometry;

say molecular-mass('SO2');
# 64.058

say balance-chemical-equation('C2H5OH + O2 = H2O + CO2');
# [1*C2H5OH + 3*O2 -> 2*CO2 + 3*H2O]

The package has also functions for chemical element data retrieval and functions that convert between chemical names, symbols/abbreviations, and atomic numbers.

Here are a couple of examples:

say atomic-number('actinium');
# 89

say chemical-symbol('ガリウム');
# Ga

Remark: Multiple languages can be used for the names of the chemical elements. The corresponding functions automatically detect the language.

Remark: At this point the package has standard element names in the languages: Bulgarian, German, Greek, English, Japanese, Persian, Polish, Russian, and Spanish. Adding new languages is easily achieved by adding CSV files into the resources directory.

Related work

The package Chemistry::Elements developed by Brian D. Foy, [BF1], also has functions that convert between chemical names, symbols/abbreviations, and atomic numbers. (Several languages are supported.)

Mathematica / Wolfram Language (WL) has the function ElementData, [WRI1].

In 2007 I wrote the original versions of the chemical equation balancing and molecular functionalities in WolframAlpha. See for example this output.

Installation

To install the package in Raku with zef installer:

zef install https://github.com/antononcube/Raku-Chemistry-Stoichiometry.git

Element data retrieval

Element data records

Element data of one or several elements can be obtained with the function chemical-element-data:

use Chemistry::Stoichiometry;
say chemical-element-data('Cl');
# {Abbreviation => Cl, AtomicNumber => 17, AtomicWeight => 35.45, Block => p, Group => 17, Name => chlorine, Period => 3, Series => Halogen, StandardName => Chlorine}

say chemical-element-data(['H', 'Li', 'Na', 'K', 'Rb', 'Cs', 'Fr']);
# ({Abbreviation => H, AtomicNumber => 1, AtomicWeight => 1.008, Block => s, Group => 1, Name => hydrogen, Period => 1, Series => Nonmetal, StandardName => Hydrogen} {Abbreviation => Li, AtomicNumber => 3, AtomicWeight => 6.94, Block => s, Group => 1, Name => lithium, Period => 2, Series => AlkaliMetal, StandardName => Lithium} {Abbreviation => Na, AtomicNumber => 11, AtomicWeight => 22.98976928, Block => s, Group => 1, Name => sodium, Period => 3, Series => AlkaliMetal, StandardName => Sodium} {Abbreviation => K, AtomicNumber => 19, AtomicWeight => 39.0983, Block => s, Group => 1, Name => potassium, Period => 4, Series => AlkaliMetal, StandardName => Potassium} {Abbreviation => Rb, AtomicNumber => 37, AtomicWeight => 85.4678, Block => s, Group => 1, Name => rubidium, Period => 5, Series => AlkaliMetal, StandardName => Rubidium} {Abbreviation => Cs, AtomicNumber => 55, AtomicWeight => 132.90545196, Block => s, Group => 1, Name => cesium, Period => 6, Series => AlkaliMetal, StandardName => Cesium} {Abbreviation => Fr, AtomicNumber => 87, AtomicWeight => 223.0, Block => s, Group => 1, Name => francium, Period => 7, Series => AlkaliMetal, StandardName => Francium})

Element names

say chemical-element('Cl');
# Chlorine

say chemical-element('Cl', 'Russian');
# Хлор

Chemical element names can be obtained using the function chemical-element-data with the adverbs :name or :standard-name:

say chemical-element-data('Cl'):name;
# Chlorine

say chemical-element-data('Cl'):standard-name;
# Chlorine

Element symbols / abbreviations

say chemical-symbol('oxygen');   # 'O' from English
# O

say chemical-symbol('кислород'); # 'O' from Bulgarian
# O

Chemical element abbreviations can be obtained using the function chemical-element-data with the adverbs :symbol or :abbr:

say chemical-element-data('oxygen'):symbol;         # 'O' from English
# O

say chemical-element-data('кислород'):abbr;         # 'O' from Bulgarian
# O

Note, that chemical-element will automatically detect the language.

Atomic numbers

say atomic-number('Cl');
# 17

say atomic-number('actinium');  # from the English name of Ac
# 89

say atomic-number('берилий');   # from the Bulgarian name of Be
# 4

Alternatively, chemical-element-data can be used with the adverbs :number or :atomic-number:

say chemical-element-data('Cl'):number;
# 17

say chemical-element-data('Cl'):atomic-number;
# 17

Atomic weights

say atomic-weight('Se');
# 78.971

say atomic-weight('ガリウム');  # from the Japanese name of Ga
# 69.723

Alternatively, chemical-element-data can be used with the adverbs :weight or :atomic-weight:

say chemical-element-data('Cl'):weight;
# 35.45

say chemical-element-data('Cl'):atomic-weight;
# 35.45

Stoichiometry procedures

The functions molecular-mass and balance-chemical-equation are based on a parser for Simplified Molecular-Input Line-Entry System (SMILES), [OS1].

Molecular mass

Molecular mass for a compound:

say molecular-mass('SO2');
# 64.058

Molecular masses of the sides of a chemical equation:

say molecular-mass('C2H5OH + O2 -> H2O + CO2');
# 78.06700000000001 => 62.024

Note that the masses in the output above are different because the equation is not balanced.

Equation balancing

For a given chemical equation the function balance-chemical-equation returns a list of balanced equations.

say balance-chemical-equation('C2H5OH + O2 = H2O + CO2');
# [1*C2H5OH + 3*O2 -> 2*CO2 + 3*H2O]

say balance-chemical-equation( 'K4Fe(CN)6 + H2SO4 + H2O = K2SO4 + FeSO4 + (NH4)2SO4 + CO' );
# [6*H2O + 6*H2SO4 + 1*K4Fe(CN)6 -> 3*(NH4)2SO4 + 6*CO + 1*FeSO4 + 2*K2SO4]

Remark: The result of the balancing is a list because certain chemical equations can be balanced in several ways corresponding to different reactions.

TODO

In order of importance, most important are first:

1. Extensive tests:

   • Chemical data retrieval

   • Chemical compound formulae parser

   • Molecular mass calculation

   • Chemical equation balancing

2. Chemical element names translation function. (Say, from Bulgarian to Persian.)

3. Inverse look-up from atomic weight to chemical element(s).

4. Extensive documentation.

5. Handling of semicolon separated input.

   • For the data functions. E.g. atomic-weight('Cl; O; Mn').

   • For the parser-interpreter functions. E.g. molecular-mass('FeSO4; H2O; CO2').

6. Parsing of (pre-)balanced chemical equations.

7. Recognition of chemical compound names.

   • This requires the development of a separate chemical entities package.

8. Element data in more languages.

References

[BF1] Brian D. Foy, Chemistry::Elements Raku package, (2016-2018), GitHub/briandfoy.

[CJ1] Craig A. James, OpenSMILES specification, (2007-2016), OpenSMILES.org.

[WRI1] Wolfram Research, ElementData, Wolfram Language function, (2007), (updated 2014), Wolfram Language System Documentation Center.