Input interpretation
Cu(OH)_2 copper hydroxide + NH_4OH ammonium hydroxide ⟶ H_2O water + Cu(NH3)4(OH)2
Balanced equation
Balance the chemical equation algebraically: Cu(OH)_2 + NH_4OH ⟶ H_2O + Cu(NH3)4(OH)2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cu(OH)_2 + c_2 NH_4OH ⟶ c_3 H_2O + c_4 Cu(NH3)4(OH)2 Set the number of atoms in the reactants equal to the number of atoms in the products for Cu, H, O and N: Cu: | c_1 = c_4 H: | 2 c_1 + 5 c_2 = 2 c_3 + 14 c_4 O: | 2 c_1 + c_2 = c_3 + 2 c_4 N: | c_2 = 4 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 = 4 c_3 = 4 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Cu(OH)_2 + 4 NH_4OH ⟶ 4 H_2O + Cu(NH3)4(OH)2
Structures
+ ⟶ + Cu(NH3)4(OH)2
Names
copper hydroxide + ammonium hydroxide ⟶ water + Cu(NH3)4(OH)2
Equilibrium constant
Construct the equilibrium constant, K, expression for: Cu(OH)_2 + NH_4OH ⟶ H_2O + Cu(NH3)4(OH)2 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 + 4 NH_4OH ⟶ 4 H_2O + Cu(NH3)4(OH)2 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 NH_4OH | 4 | -4 H_2O | 4 | 4 Cu(NH3)4(OH)2 | 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) NH_4OH | 4 | -4 | ([NH4OH])^(-4) H_2O | 4 | 4 | ([H2O])^4 Cu(NH3)4(OH)2 | 1 | 1 | [Cu(NH3)4(OH)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(OH)2])^(-1) ([NH4OH])^(-4) ([H2O])^4 [Cu(NH3)4(OH)2] = (([H2O])^4 [Cu(NH3)4(OH)2])/([Cu(OH)2] ([NH4OH])^4)
Rate of reaction
Construct the rate of reaction expression for: Cu(OH)_2 + NH_4OH ⟶ H_2O + Cu(NH3)4(OH)2 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 + 4 NH_4OH ⟶ 4 H_2O + Cu(NH3)4(OH)2 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 NH_4OH | 4 | -4 H_2O | 4 | 4 Cu(NH3)4(OH)2 | 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) NH_4OH | 4 | -4 | -1/4 (Δ[NH4OH])/(Δt) H_2O | 4 | 4 | 1/4 (Δ[H2O])/(Δt) Cu(NH3)4(OH)2 | 1 | 1 | (Δ[Cu(NH3)4(OH)2])/(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) = -1/4 (Δ[NH4OH])/(Δt) = 1/4 (Δ[H2O])/(Δt) = (Δ[Cu(NH3)4(OH)2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| copper hydroxide | ammonium hydroxide | water | Cu(NH3)4(OH)2 formula | Cu(OH)_2 | NH_4OH | H_2O | Cu(NH3)4(OH)2 Hill formula | CuH_2O_2 | H_5NO | H_2O | H14CuN4O2 name | copper hydroxide | ammonium hydroxide | water | IUPAC name | copper dihydroxide | ammonium hydroxide | water |
Substance properties
| copper hydroxide | ammonium hydroxide | water | Cu(NH3)4(OH)2 molar mass | 97.56 g/mol | 35.046 g/mol | 18.015 g/mol | 165.68 g/mol phase | | aqueous (at STP) | liquid (at STP) | melting point | | -57.5 °C | 0 °C | boiling point | | 36 °C | 99.9839 °C | density | | 0.9 g/cm^3 | 1 g/cm^3 | solubility in water | | very soluble | | surface tension | | | 0.0728 N/m | dynamic viscosity | | | 8.9×10^-4 Pa s (at 25 °C) | odor | | | odorless |
Units