Al + FeCl3 = Fe + AlCl3

Al aluminum + FeCl_3 iron(III) chloride ⟶ Fe iron + AlCl_3 aluminum chloride

Balance the chemical equation algebraically: Al + FeCl_3 ⟶ Fe + AlCl_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Al + c_2 FeCl_3 ⟶ c_3 Fe + c_4 AlCl_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Al, Cl and Fe: Al: | c_1 = c_4 Cl: | 3 c_2 = 3 c_4 Fe: | 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_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: | | Al + FeCl_3 ⟶ Fe + AlCl_3

+ ⟶ +

aluminum + iron(III) chloride ⟶ iron + aluminum chloride

| aluminum | iron(III) chloride | iron | aluminum chloride molecular enthalpy | 0 kJ/mol | -399.5 kJ/mol | 0 kJ/mol | -704.2 kJ/mol total enthalpy | 0 kJ/mol | -399.5 kJ/mol | 0 kJ/mol | -704.2 kJ/mol | H_initial = -399.5 kJ/mol | | H_final = -704.2 kJ/mol | ΔH_rxn^0 | -704.2 kJ/mol - -399.5 kJ/mol = -304.7 kJ/mol (exothermic) | | |

Construct the equilibrium constant, K, expression for: Al + FeCl_3 ⟶ Fe + AlCl_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: Al + FeCl_3 ⟶ Fe + AlCl_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 Al | 1 | -1 FeCl_3 | 1 | -1 Fe | 1 | 1 AlCl_3 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Al | 1 | -1 | ([Al])^(-1) FeCl_3 | 1 | -1 | ([FeCl3])^(-1) Fe | 1 | 1 | [Fe] AlCl_3 | 1 | 1 | [AlCl3] 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 = ([Al])^(-1) ([FeCl3])^(-1) [Fe] [AlCl3] = ([Fe] [AlCl3])/([Al] [FeCl3])

Construct the rate of reaction expression for: Al + FeCl_3 ⟶ Fe + AlCl_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: Al + FeCl_3 ⟶ Fe + AlCl_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 Al | 1 | -1 FeCl_3 | 1 | -1 Fe | 1 | 1 AlCl_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 Al | 1 | -1 | -(Δ[Al])/(Δt) FeCl_3 | 1 | -1 | -(Δ[FeCl3])/(Δt) Fe | 1 | 1 | (Δ[Fe])/(Δt) AlCl_3 | 1 | 1 | (Δ[AlCl3])/(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[Al])/(Δt) = -(Δ[FeCl3])/(Δt) = (Δ[Fe])/(Δt) = (Δ[AlCl3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| aluminum | iron(III) chloride | iron | aluminum chloride formula | Al | FeCl_3 | Fe | AlCl_3 Hill formula | Al | Cl_3Fe | Fe | AlCl_3 name | aluminum | iron(III) chloride | iron | aluminum chloride IUPAC name | aluminum | trichloroiron | iron | trichloroalumane

| aluminum | iron(III) chloride | iron | aluminum chloride molar mass | 26.9815385 g/mol | 162.2 g/mol | 55.845 g/mol | 133.3 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) melting point | 660.4 °C | 304 °C | 1535 °C | 190 °C boiling point | 2460 °C | | 2750 °C | density | 2.7 g/cm^3 | | 7.874 g/cm^3 | solubility in water | insoluble | | insoluble | surface tension | 0.817 N/m | | | dynamic viscosity | 1.5×10^-4 Pa s (at 760 °C) | | | odor | odorless | | |