NH4HCO3 = H2O + CO2 + NH3

NH_4HCO_3 ammonium bicarbonate ⟶ H_2O water + CO_2 carbon dioxide + NH_3 ammonia

Balance the chemical equation algebraically: NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 NH_4HCO_3 ⟶ c_2 H_2O + c_3 CO_2 + c_4 NH_3 Set the number of atoms in the reactants equal to the number of atoms in the products for C, H, N and O: C: | c_1 = c_3 H: | 5 c_1 = 2 c_2 + 3 c_4 N: | c_1 = c_4 O: | 3 c_1 = c_2 + 2 c_3 Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 1 c_3 = 1 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3

⟶ + +

ammonium bicarbonate ⟶ water + carbon dioxide + ammonia

Construct the equilibrium constant, K, expression for: NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3 Plan: • Balance the chemical equation. • Determine the stoichiometric numbers. • Assemble the activity expression for each chemical species. • Use the activity expressions to build the equilibrium constant expression. Write the balanced chemical equation: NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3 Assign stoichiometric numbers, ν_i, using the stoichiometric coefficients, c_i, from the balanced chemical equation in the following manner: ν_i = -c_i for reactants and ν_i = c_i for products: chemical species | c_i | ν_i NH_4HCO_3 | 1 | -1 H_2O | 1 | 1 CO_2 | 1 | 1 NH_3 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression NH_4HCO_3 | 1 | -1 | ([NH4HCO3])^(-1) H_2O | 1 | 1 | [H2O] CO_2 | 1 | 1 | [CO2] NH_3 | 1 | 1 | [NH3] The equilibrium constant symbol in the concentration basis is: K_c Mulitply the activity expressions to arrive at the K_c expression: Answer: | | K_c = ([NH4HCO3])^(-1) [H2O] [CO2] [NH3] = ([H2O] [CO2] [NH3])/([NH4HCO3])

Construct the rate of reaction expression for: NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3 Plan: • Balance the chemical equation. • Determine the stoichiometric numbers. • Assemble the rate term for each chemical species. • Write the rate of reaction expression. Write the balanced chemical equation: NH_4HCO_3 ⟶ H_2O + CO_2 + NH_3 Assign stoichiometric numbers, ν_i, using the stoichiometric coefficients, c_i, from the balanced chemical equation in the following manner: ν_i = -c_i for reactants and ν_i = c_i for products: chemical species | c_i | ν_i NH_4HCO_3 | 1 | -1 H_2O | 1 | 1 CO_2 | 1 | 1 NH_3 | 1 | 1 The rate term for each chemical species, B_i, is 1/ν_i(Δ[B_i])/(Δt) where [B_i] is the amount concentration and t is time: chemical species | c_i | ν_i | rate term NH_4HCO_3 | 1 | -1 | -(Δ[NH4HCO3])/(Δt) H_2O | 1 | 1 | (Δ[H2O])/(Δt) CO_2 | 1 | 1 | (Δ[CO2])/(Δt) NH_3 | 1 | 1 | (Δ[NH3])/(Δt) (for infinitesimal rate of change, replace Δ with d) Set the rate terms equal to each other to arrive at the rate expression: Answer: | | rate = -(Δ[NH4HCO3])/(Δt) = (Δ[H2O])/(Δt) = (Δ[CO2])/(Δt) = (Δ[NH3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| ammonium bicarbonate | water | carbon dioxide | ammonia formula | NH_4HCO_3 | H_2O | CO_2 | NH_3 Hill formula | CH_5NO_3 | H_2O | CO_2 | H_3N name | ammonium bicarbonate | water | carbon dioxide | ammonia IUPAC name | ammonium hydrogen carbonate | water | carbon dioxide | ammonia