FeCl3 + Cu(OH)2 = CuCl2 + Fe(OH)3

FeCl_3 iron(III) chloride + Cu(OH)_2 copper hydroxide ⟶ CuCl_2 copper(II) chloride + Fe(OH)_3 iron(III) hydroxide

Balance the chemical equation algebraically: FeCl_3 + Cu(OH)_2 ⟶ CuCl_2 + Fe(OH)_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 FeCl_3 + c_2 Cu(OH)_2 ⟶ c_3 CuCl_2 + c_4 Fe(OH)_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, Fe, Cu, H and O: Cl: | 3 c_1 = 2 c_3 Fe: | c_1 = c_4 Cu: | c_2 = c_3 H: | 2 c_2 = 3 c_4 O: | 2 c_2 = 3 c_4 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 FeCl_3 + 3 Cu(OH)_2 ⟶ 3 CuCl_2 + 2 Fe(OH)_3

+ ⟶ +

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

Construct the equilibrium constant, K, expression for: FeCl_3 + Cu(OH)_2 ⟶ CuCl_2 + Fe(OH)_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 FeCl_3 + 3 Cu(OH)_2 ⟶ 3 CuCl_2 + 2 Fe(OH)_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 FeCl_3 | 2 | -2 Cu(OH)_2 | 3 | -3 CuCl_2 | 3 | 3 Fe(OH)_3 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression FeCl_3 | 2 | -2 | ([FeCl3])^(-2) Cu(OH)_2 | 3 | -3 | ([Cu(OH)2])^(-3) CuCl_2 | 3 | 3 | ([CuCl2])^3 Fe(OH)_3 | 2 | 2 | ([Fe(OH)3])^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 = ([FeCl3])^(-2) ([Cu(OH)2])^(-3) ([CuCl2])^3 ([Fe(OH)3])^2 = (([CuCl2])^3 ([Fe(OH)3])^2)/(([FeCl3])^2 ([Cu(OH)2])^3)

Construct the rate of reaction expression for: FeCl_3 + Cu(OH)_2 ⟶ CuCl_2 + Fe(OH)_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 FeCl_3 + 3 Cu(OH)_2 ⟶ 3 CuCl_2 + 2 Fe(OH)_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 FeCl_3 | 2 | -2 Cu(OH)_2 | 3 | -3 CuCl_2 | 3 | 3 Fe(OH)_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 FeCl_3 | 2 | -2 | -1/2 (Δ[FeCl3])/(Δt) Cu(OH)_2 | 3 | -3 | -1/3 (Δ[Cu(OH)2])/(Δt) CuCl_2 | 3 | 3 | 1/3 (Δ[CuCl2])/(Δt) Fe(OH)_3 | 2 | 2 | 1/2 (Δ[Fe(OH)3])/(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[FeCl3])/(Δt) = -1/3 (Δ[Cu(OH)2])/(Δt) = 1/3 (Δ[CuCl2])/(Δt) = 1/2 (Δ[Fe(OH)3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| iron(III) chloride | copper hydroxide | copper(II) chloride | iron(III) hydroxide formula | FeCl_3 | Cu(OH)_2 | CuCl_2 | Fe(OH)_3 Hill formula | Cl_3Fe | CuH_2O_2 | Cl_2Cu | FeH_3O_3 name | iron(III) chloride | copper hydroxide | copper(II) chloride | iron(III) hydroxide IUPAC name | trichloroiron | copper dihydroxide | dichlorocopper | ferric trihydroxide

| iron(III) chloride | copper hydroxide | copper(II) chloride | iron(III) hydroxide molar mass | 162.2 g/mol | 97.56 g/mol | 134.4 g/mol | 106.87 g/mol phase | solid (at STP) | | solid (at STP) | melting point | 304 °C | | 620 °C | density | | | 3.386 g/cm^3 |