úÎ ¯ –   Safe-Inferred"Find element by its atomic number  atomicNumber (element 8) == 8 Find element by its symbol * atomicNumber (elementBySymbol "O") == 8 'Show number of electrons in each shell  let e = element 8  shellElectrons e == [2, 6] Number of valance electrons  let e = element 8  valanceElectrons e == 6 %Number of covalent bounds in element  let e = element 8  covalentBounds e == 2       Safe-Inferred Parse formula ? parseFormula "C2H4" `shouldBe` Formula [("C", 2), ("H", 4)]            radium-0.2Chemistry.ElementChemistry.FormulaElement atomicNumberelementelementBySymbolshellElectronsvalanceElectronscovalentBoundsFormula parseFormulaUnknownsymbol_name_weightptablesubshellMaxElectronsshellConfigGen fillShellsformula elementSymbol