Module: AsciiChem::PeriodicTable

Defined in:
lib/asciichem/periodic_table.rb

Overview

Periodic table as a single source of truth for element data. Used by linter checks (element validation, isotope sanity, valence) and any future code that needs chemically-grounded defaults.

Adding a new field (e.g. covalent radius for layout, common oxidation states for redox checks) means adding one column to Element and populating it across ELEMENTS — no other code changes.

Defined Under Namespace

Classes: Element

Constant Summary collapse

ELEMENTS =

Subset covering the elements chemistry most commonly deals with. Each entry: symbol => Element. Adding more elements is one line per element; the linter picks them up automatically.

{
  # Period 1
  "H"  => Element.new(symbol: "H",  atomic_number: 1,  max_valence: 1),
  "He" => Element.new(symbol: "He", atomic_number: 2,  max_valence: 0),
  # Period 2
  "Li" => Element.new(symbol: "Li", atomic_number: 3,  max_valence: 1),
  "Be" => Element.new(symbol: "Be", atomic_number: 4,  max_valence: 2),
  "B"  => Element.new(symbol: "B",  atomic_number: 5,  max_valence: 3),
  "C"  => Element.new(symbol: "C",  atomic_number: 6,  max_valence: 4),
  "N"  => Element.new(symbol: "N",  atomic_number: 7,  max_valence: 3),
  "O"  => Element.new(symbol: "O",  atomic_number: 8,  max_valence: 2),
  "F"  => Element.new(symbol: "F",  atomic_number: 9,  max_valence: 1),
  "Ne" => Element.new(symbol: "Ne", atomic_number: 10, max_valence: 0),
  # Period 3
  "Na" => Element.new(symbol: "Na", atomic_number: 11, max_valence: 1),
  "Mg" => Element.new(symbol: "Mg", atomic_number: 12, max_valence: 2),
  "Al" => Element.new(symbol: "Al", atomic_number: 13, max_valence: 3),
  "Si" => Element.new(symbol: "Si", atomic_number: 14, max_valence: 4),
  "P"  => Element.new(symbol: "P",  atomic_number: 15, max_valence: 5),
  "S"  => Element.new(symbol: "S",  atomic_number: 16, max_valence: 6),
  "Cl" => Element.new(symbol: "Cl", atomic_number: 17, max_valence: 1),
  "Ar" => Element.new(symbol: "Ar", atomic_number: 18, max_valence: 0),
  # Period 4 (common)
  "K"  => Element.new(symbol: "K",  atomic_number: 19, max_valence: 1),
  "Ca" => Element.new(symbol: "Ca", atomic_number: 20, max_valence: 2),
  "Sc" => Element.new(symbol: "Sc", atomic_number: 21, max_valence: 3),
  "Ti" => Element.new(symbol: "Ti", atomic_number: 22, max_valence: 4),
  "V"  => Element.new(symbol: "V",  atomic_number: 23, max_valence: 5),
  "Cr" => Element.new(symbol: "Cr", atomic_number: 24, max_valence: 6),
  "Mn" => Element.new(symbol: "Mn", atomic_number: 25, max_valence: 7),
  "Fe" => Element.new(symbol: "Fe", atomic_number: 26, max_valence: 6),
  "Co" => Element.new(symbol: "Co", atomic_number: 27, max_valence: 4),
  "Ni" => Element.new(symbol: "Ni", atomic_number: 28, max_valence: 4),
  "Cu" => Element.new(symbol: "Cu", atomic_number: 29, max_valence: 4),
  "Zn" => Element.new(symbol: "Zn", atomic_number: 30, max_valence: 2),
  "Ga" => Element.new(symbol: "Ga", atomic_number: 31, max_valence: 3),
  "Ge" => Element.new(symbol: "Ge", atomic_number: 32, max_valence: 4),
  "As" => Element.new(symbol: "As", atomic_number: 33, max_valence: 3),
  "Se" => Element.new(symbol: "Se", atomic_number: 34, max_valence: 2),
  "Br" => Element.new(symbol: "Br", atomic_number: 35, max_valence: 1),
  "Kr" => Element.new(symbol: "Kr", atomic_number: 36, max_valence: 0),
  # Period 5 (common)
  "Rb" => Element.new(symbol: "Rb", atomic_number: 37, max_valence: 1),
  "Sr" => Element.new(symbol: "Sr", atomic_number: 38, max_valence: 2),
  "Y"  => Element.new(symbol: "Y",  atomic_number: 39, max_valence: 3),
  "Zr" => Element.new(symbol: "Zr", atomic_number: 40, max_valence: 4),
  "Nb" => Element.new(symbol: "Nb", atomic_number: 41, max_valence: 5),
  "Mo" => Element.new(symbol: "Mo", atomic_number: 42, max_valence: 6),
  "Tc" => Element.new(symbol: "Tc", atomic_number: 43, max_valence: 6),
  "Ru" => Element.new(symbol: "Ru", atomic_number: 44, max_valence: 6),
  "Rh" => Element.new(symbol: "Rh", atomic_number: 45, max_valence: 6),
  "Pd" => Element.new(symbol: "Pd", atomic_number: 46, max_valence: 4),
  "Ag" => Element.new(symbol: "Ag", atomic_number: 47, max_valence: 4),
  "Cd" => Element.new(symbol: "Cd", atomic_number: 48, max_valence: 2),
  "In" => Element.new(symbol: "In", atomic_number: 49, max_valence: 3),
  "Sn" => Element.new(symbol: "Sn", atomic_number: 50, max_valence: 4),
  "Sb" => Element.new(symbol: "Sb", atomic_number: 51, max_valence: 3),
  "Te" => Element.new(symbol: "Te", atomic_number: 52, max_valence: 2),
  "I"  => Element.new(symbol: "I",  atomic_number: 53, max_valence: 1),
  "Xe" => Element.new(symbol: "Xe", atomic_number: 54, max_valence: 0),
  # Period 6 (common)
  "Cs" => Element.new(symbol: "Cs", atomic_number: 55, max_valence: 1),
  "Ba" => Element.new(symbol: "Ba", atomic_number: 56, max_valence: 2),
  "W"  => Element.new(symbol: "W",  atomic_number: 74, max_valence: 6),
  "Pt" => Element.new(symbol: "Pt", atomic_number: 78, max_valence: 4),
  "Au" => Element.new(symbol: "Au", atomic_number: 79, max_valence: 6),
  "Hg" => Element.new(symbol: "Hg", atomic_number: 80, max_valence: 2),
  "Tl" => Element.new(symbol: "Tl", atomic_number: 81, max_valence: 3),
  "Pb" => Element.new(symbol: "Pb", atomic_number: 82, max_valence: 4),
  "Bi" => Element.new(symbol: "Bi", atomic_number: 83, max_valence: 3),
  # Period 7 (common)
  "U"  => Element.new(symbol: "U",  atomic_number: 92, max_valence: 6)
}.freeze

Class Method Summary collapse

Class Method Details

.atomic_number(symbol) ⇒ Object 



100
101
102
 
# File 'lib/asciichem/periodic_table.rb', line 100

def self.atomic_number(symbol)
  element(symbol.to_s)&.atomic_number
end

.element(symbol) ⇒ Object 



92
93
94
 
# File 'lib/asciichem/periodic_table.rb', line 92

def self.element(symbol)
  ELEMENTS[symbol.to_s]
end

.known?(symbol) ⇒ Boolean

Returns:

  • (Boolean) 


96
97
98
 
# File 'lib/asciichem/periodic_table.rb', line 96

def self.known?(symbol)
  ELEMENTS.key?(symbol.to_s)
end

.max_valence(symbol) ⇒ Object 



104
105
106
 
# File 'lib/asciichem/periodic_table.rb', line 104

def self.max_valence(symbol)
  element(symbol.to_s)&.max_valence
end

.symbols ⇒ Object 



108
109
110
 
# File 'lib/asciichem/periodic_table.rb', line 108

def self.symbols
  ELEMENTS.keys
end