Cu + CuCl2 = CuCl

Cu copper + CuCl_2 copper(II) chloride ⟶ CuCl cuprous chloride

Balance the chemical equation algebraically: Cu + CuCl_2 ⟶ CuCl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cu + c_2 CuCl_2 ⟶ c_3 CuCl Set the number of atoms in the reactants equal to the number of atoms in the products for Cu and Cl: Cu: | c_1 + c_2 = c_3 Cl: | 2 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 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Cu + CuCl_2 ⟶ 2 CuCl

+ ⟶

copper + copper(II) chloride ⟶ cuprous chloride

| copper | copper(II) chloride | cuprous chloride molecular enthalpy | 0 kJ/mol | -220.1 kJ/mol | -137.2 kJ/mol total enthalpy | 0 kJ/mol | -220.1 kJ/mol | -274.4 kJ/mol | H_initial = -220.1 kJ/mol | | H_final = -274.4 kJ/mol ΔH_rxn^0 | -274.4 kJ/mol - -220.1 kJ/mol = -54.3 kJ/mol (exothermic) | |

Construct the equilibrium constant, K, expression for: Cu + CuCl_2 ⟶ CuCl 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: Cu + CuCl_2 ⟶ 2 CuCl 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 Cu | 1 | -1 CuCl_2 | 1 | -1 CuCl | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Cu | 1 | -1 | ([Cu])^(-1) CuCl_2 | 1 | -1 | ([CuCl2])^(-1) CuCl | 2 | 2 | ([CuCl])^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 = ([Cu])^(-1) ([CuCl2])^(-1) ([CuCl])^2 = ([CuCl])^2/([Cu] [CuCl2])

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

| copper | copper(II) chloride | cuprous chloride formula | Cu | CuCl_2 | CuCl Hill formula | Cu | Cl_2Cu | ClCu name | copper | copper(II) chloride | cuprous chloride IUPAC name | copper | dichlorocopper |

| copper | copper(II) chloride | cuprous chloride molar mass | 63.546 g/mol | 134.4 g/mol | 99 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) melting point | 1083 °C | 620 °C | 430 °C boiling point | 2567 °C | | 1490 °C density | 8.96 g/cm^3 | 3.386 g/cm^3 | 4.145 g/cm^3 solubility in water | insoluble | | odor | odorless | |