def test_mix_b():
mu_h2 = cm.mu_gas('H2', 773.15)
mu_n2 = cm.mu_gas('N2', 773.15)
mw_h2 = cm.mw('H2')
mw_n2 = cm.mw('N2')
mu_mix = cm.mu_herning([mu_h2, mu_n2], [mw_h2, mw_n2], [0.85, 0.15])
assert mu_mix == approx(252.81, rel=1e-2)
def test_mix_b():
mw_h2 = cm.mw('H2')
mw_n2 = cm.mw('N2')
mw_ch4 = cm.mw('CH4')
mw = cm.mw_mix([mw_h2, mw_n2, mw_ch4], [0.4, 0.1, 0.5])
assert mw == approx(11.6293, rel=1e-2)
def test_mix_a():
mw_h2 = cm.mw('H2')
mw_n2 = cm.mw('N2')
mw = cm.mw_mix([mw_h2, mw_n2], [0.8, 0.2])
assert mw == approx(7.2156, rel=1e-2)
def test_ammonium_sulfate():
mw = cm.mw('(NH4)2SO4')
assert mw == approx(132.13, rel=1e-2)
def test_methane():
mw = cm.mw('CH4')
assert mw == approx(16.04, rel=1e-2)
def test_carbon():
mw = cm.mw('C')
assert mw == 12.011
"""
Determine molecular weight of an element, compound, or gas mixture.
"""
import chemics as cm
formula = 'C'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = 'Co'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = 'CH4'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = '(CO2)2'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = 'Ca(C2H3O2)2'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = '(NH4)2SO4'
mw = cm.mw(formula)
print(f'Molecular weight of {formula} = {mw:.2f} g/mol')
formula = '(NH4)(NO3)'
def _eq_properties(self, eq_items):
"""
Determine properties for each item in reactants or products.
"""
eq_names = []
eq_moles = []
eq_species = []
eq_molwts = []
eq_masses = []
eq_elements = Counter()
for item in eq_items:
# number of moles and name for each item
if item[0].isdigit():
item = item.split()
mol = float(item[0])
name = item[1]
eq_names.append(name)
eq_moles.append(mol)
else:
mol = 1.0
name = item
eq_names.append(name)
eq_moles.append(mol)
# species for each item is chemical formula specified in names
# dictonary or as chemical formula (name) in the chemical equation
# note - species is used for the molecular weight and elements
if (self.names is not None) and (name in self.names.keys()):
sp = self.names[name]
eq_species.append(sp)
else:
sp = name
eq_species.append(sp)
# masses and molecular weights for each item
mw = cm.mw(sp)
mass = mol * mw
eq_molwts.append(cm.mw(sp))
eq_masses.append(mass)
# count elements from each chemical species
rex = re.findall('([A-Z][a-z]?)([0-9]*)', sp)
for r in rex:
element = r[0]
if r[1] == '':
atoms = 1.0
else:
atoms = float(r[1])
# dict where key is element and value is number of atoms such as {'C': 6.0}
d = {element: atoms * mol}
eq_elements.update(d)
# sum of moles and masses
eq_sum_moles = sum(eq_moles)
eq_sum_masses = sum(eq_masses)
# mole fractions and mass fractions
eq_mol_fracs = [m / eq_sum_moles for m in eq_moles]
eq_mass_fracs = [m / eq_sum_masses for m in eq_masses]
# dataframe for properties
cols = eq_names
idx = ['moles', 'species', 'molwt', 'mass', 'molfrac', 'massfrac']
df = pd.DataFrame(columns=cols, index=idx)
df.loc['moles'] = eq_moles
df.loc['species'] = eq_species
df.loc['molwt'] = eq_molwts
df.loc['mass'] = eq_masses
df.loc['molfrac'] = eq_mol_fracs
df.loc['massfrac'] = eq_mass_fracs
return df, dict(eq_elements), eq_sum_moles, eq_sum_masses