Python Language ChemPy - python package Chemical equilibria


Example

 from chempy import Equilibrium
 from chempy.chemistry import Species
 water_autop = Equilibrium({'H2O'}, {'H+', 'OH-'}, 10**-14)  # unit "molar" assumed
 ammonia_prot = Equilibrium({'NH4+'}, {'NH3', 'H+'}, 10**-9.24)  # same here
 from chempy.equilibria import EqSystem
 substances = map(Species.from_formula, 'H2O OH- H+ NH3 NH4+'.split())
 eqsys = EqSystem([water_autop, ammonia_prot], substances)
 print('\n'.join(map(str, eqsys.rxns)))  # "rxns" short for "reactions"
H2O = H+ + OH-; 1e-14
NH4+ = H+ + NH3; 5.75e-10
 from collections import defaultdict
 init_conc = defaultdict(float, {'H2O': 1, 'NH3': 0.1})
 x, sol, sane = eqsys.root(init_conc)
 assert sol['success'] and sane
 print(sorted(sol.keys()))  # see package "pyneqsys" for more info
['fun', 'intermediate_info', 'internal_x_vecs', 'nfev', 'njev', 'success', 'x', 'x_vecs']
 print(', '.join('%.2g' % v for v in x))
1, 0.0013, 7.6e-12, 0.099, 0.0013