Fe + CuCl2 = Cu + FeCl3

Fe iron + CuCl_2 copper(II) chloride ⟶ Cu copper + FeCl_3 iron(III) chloride

Balance the chemical equation algebraically: Fe + CuCl_2 ⟶ Cu + FeCl_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Fe + c_2 CuCl_2 ⟶ c_3 Cu + c_4 FeCl_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Fe, Cl and Cu: Fe: | c_1 = c_4 Cl: | 2 c_2 = 3 c_4 Cu: | 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 = 3/2 c_3 = 3/2 c_4 = 1 Multiply by the least common denominator, 2, to eliminate fractional coefficients: c_1 = 2 c_2 = 3 c_3 = 3 c_4 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 Fe + 3 CuCl_2 ⟶ 3 Cu + 2 FeCl_3

+ ⟶ +

iron + copper(II) chloride ⟶ copper + iron(III) chloride

| iron | copper(II) chloride | copper | iron(III) chloride molecular enthalpy | 0 kJ/mol | -220.1 kJ/mol | 0 kJ/mol | -399.5 kJ/mol total enthalpy | 0 kJ/mol | -660.3 kJ/mol | 0 kJ/mol | -799 kJ/mol | H_initial = -660.3 kJ/mol | | H_final = -799 kJ/mol | ΔH_rxn^0 | -799 kJ/mol - -660.3 kJ/mol = -138.7 kJ/mol (exothermic) | | |

Construct the equilibrium constant, K, expression for: Fe + CuCl_2 ⟶ Cu + FeCl_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: 2 Fe + 3 CuCl_2 ⟶ 3 Cu + 2 FeCl_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 Fe | 2 | -2 CuCl_2 | 3 | -3 Cu | 3 | 3 FeCl_3 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Fe | 2 | -2 | ([Fe])^(-2) CuCl_2 | 3 | -3 | ([CuCl2])^(-3) Cu | 3 | 3 | ([Cu])^3 FeCl_3 | 2 | 2 | ([FeCl3])^2 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 = ([Fe])^(-2) ([CuCl2])^(-3) ([Cu])^3 ([FeCl3])^2 = (([Cu])^3 ([FeCl3])^2)/(([Fe])^2 ([CuCl2])^3)

Construct the rate of reaction expression for: Fe + CuCl_2 ⟶ Cu + FeCl_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: 2 Fe + 3 CuCl_2 ⟶ 3 Cu + 2 FeCl_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 Fe | 2 | -2 CuCl_2 | 3 | -3 Cu | 3 | 3 FeCl_3 | 2 | 2 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 Fe | 2 | -2 | -1/2 (Δ[Fe])/(Δt) CuCl_2 | 3 | -3 | -1/3 (Δ[CuCl2])/(Δt) Cu | 3 | 3 | 1/3 (Δ[Cu])/(Δt) FeCl_3 | 2 | 2 | 1/2 (Δ[FeCl3])/(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 = -1/2 (Δ[Fe])/(Δt) = -1/3 (Δ[CuCl2])/(Δt) = 1/3 (Δ[Cu])/(Δt) = 1/2 (Δ[FeCl3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| iron | copper(II) chloride | copper | iron(III) chloride formula | Fe | CuCl_2 | Cu | FeCl_3 Hill formula | Fe | Cl_2Cu | Cu | Cl_3Fe name | iron | copper(II) chloride | copper | iron(III) chloride IUPAC name | iron | dichlorocopper | copper | trichloroiron

| iron | copper(II) chloride | copper | iron(III) chloride molar mass | 55.845 g/mol | 134.4 g/mol | 63.546 g/mol | 162.2 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | solid (at STP) melting point | 1535 °C | 620 °C | 1083 °C | 304 °C boiling point | 2750 °C | | 2567 °C | density | 7.874 g/cm^3 | 3.386 g/cm^3 | 8.96 g/cm^3 | solubility in water | insoluble | | insoluble | odor | | | odorless |