HCl + Fe2O3 = H2O + FeCl3

HCl (hydrogen chloride) + Fe_2O_3 (iron(III) oxide) ⟶ H_2O (water) + FeCl_3 (iron(III) chloride)

Balance the chemical equation algebraically: HCl + Fe_2O_3 ⟶ H_2O + FeCl_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HCl + c_2 Fe_2O_3 ⟶ c_3 H_2O + c_4 FeCl_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, H, Fe and O: Cl: | c_1 = 3 c_4 H: | c_1 = 2 c_3 Fe: | 2 c_2 = c_4 O: | 3 c_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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 6 c_2 = 1 c_3 = 3 c_4 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 6 HCl + Fe_2O_3 ⟶ 3 H_2O + 2 FeCl_3

+ ⟶ +

hydrogen chloride + iron(III) oxide ⟶ water + iron(III) chloride

| hydrogen chloride | iron(III) oxide | water | iron(III) chloride molecular enthalpy | -92.3 kJ/mol | -826 kJ/mol | -285.8 kJ/mol | -399.5 kJ/mol total enthalpy | -553.8 kJ/mol | -826 kJ/mol | -857.5 kJ/mol | -799 kJ/mol | H_initial = -1380 kJ/mol | | H_final = -1656 kJ/mol | ΔH_rxn^0 | -1656 kJ/mol - -1380 kJ/mol = -276.7 kJ/mol (exothermic) | | |

| hydrogen chloride | iron(III) oxide | water | iron(III) chloride molecular free energy | -95.3 kJ/mol | -742.2 kJ/mol | -237.1 kJ/mol | -334 kJ/mol total free energy | -571.8 kJ/mol | -742.2 kJ/mol | -711.3 kJ/mol | -668 kJ/mol | G_initial = -1314 kJ/mol | | G_final = -1379 kJ/mol | ΔG_rxn^0 | -1379 kJ/mol - -1314 kJ/mol = -65.3 kJ/mol (exergonic) | | |

K_c = ([H2O]^3 [FeCl3]^2)/([HCl]^6 [Fe2O3])

rate = -1/6 (Δ[HCl])/(Δt) = -(Δ[Fe2O3])/(Δt) = 1/3 (Δ[H2O])/(Δt) = 1/2 (Δ[FeCl3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen chloride | iron(III) oxide | water | iron(III) chloride formula | HCl | Fe_2O_3 | H_2O | FeCl_3 Hill formula | ClH | Fe_2O_3 | H_2O | Cl_3Fe name | hydrogen chloride | iron(III) oxide | water | iron(III) chloride IUPAC name | hydrogen chloride | | water | trichloroiron