Cu(OH)2 = H2O + CuO

Cu(OH)_2 (copper hydroxide) ⟶ H_2O (water) + CuO (cupric oxide)

Balance the chemical equation algebraically: Cu(OH)_2 ⟶ H_2O + CuO Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cu(OH)_2 ⟶ c_2 H_2O + c_3 CuO Set the number of atoms in the reactants equal to the number of atoms in the products for Cu, H and O: Cu: | c_1 = c_3 H: | 2 c_1 = 2 c_2 O: | 2 c_1 = 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 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Cu(OH)_2 ⟶ H_2O + CuO

⟶ +

copper hydroxide ⟶ water + cupric oxide

Construct the equilibrium constant, K, expression for: Cu(OH)_2 ⟶ H_2O + CuO 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(OH)_2 ⟶ H_2O + CuO 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(OH)_2 | 1 | -1 H_2O | 1 | 1 CuO | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Cu(OH)_2 | 1 | -1 | ([Cu(OH)2])^(-1) H_2O | 1 | 1 | [H2O] CuO | 1 | 1 | [CuO] 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(OH)2])^(-1) [H2O] [CuO] = ([H2O] [CuO])/([Cu(OH)2])

Construct the rate of reaction expression for: Cu(OH)_2 ⟶ H_2O + CuO 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(OH)_2 ⟶ H_2O + CuO 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(OH)_2 | 1 | -1 H_2O | 1 | 1 CuO | 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 Cu(OH)_2 | 1 | -1 | -(Δ[Cu(OH)2])/(Δt) H_2O | 1 | 1 | (Δ[H2O])/(Δt) CuO | 1 | 1 | (Δ[CuO])/(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(OH)2])/(Δt) = (Δ[H2O])/(Δt) = (Δ[CuO])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| copper hydroxide | water | cupric oxide formula | Cu(OH)_2 | H_2O | CuO Hill formula | CuH_2O_2 | H_2O | CuO name | copper hydroxide | water | cupric oxide IUPAC name | copper dihydroxide | water |

| copper hydroxide | water | cupric oxide molar mass | 97.56 g/mol | 18.015 g/mol | 79.545 g/mol phase | | liquid (at STP) | solid (at STP) melting point | | 0 °C | 1326 °C boiling point | | 99.9839 °C | 2000 °C density | | 1 g/cm^3 | 6.315 g/cm^3 solubility in water | | | insoluble surface tension | | 0.0728 N/m | dynamic viscosity | | 8.9×10^-4 Pa s (at 25 °C) | odor | | odorless |