Input interpretation
H_2O_2 hydrogen peroxide + AuCl_3 gold(III) chloride ⟶ O_2 oxygen + HCl hydrogen chloride + Au gold
Balanced equation
Balance the chemical equation algebraically: H_2O_2 + AuCl_3 ⟶ O_2 + HCl + Au Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2O_2 + c_2 AuCl_3 ⟶ c_3 O_2 + c_4 HCl + c_5 Au Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, Au and Cl: H: | 2 c_1 = c_4 O: | 2 c_1 = 2 c_3 Au: | c_2 = c_5 Cl: | 3 c_2 = 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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 3/2 c_2 = 1 c_3 = 3/2 c_4 = 3 c_5 = 1 Multiply by the least common denominator, 2, to eliminate fractional coefficients: c_1 = 3 c_2 = 2 c_3 = 3 c_4 = 6 c_5 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 3 H_2O_2 + 2 AuCl_3 ⟶ 3 O_2 + 6 HCl + 2 Au
Structures
+ ⟶ + +
Names
hydrogen peroxide + gold(III) chloride ⟶ oxygen + hydrogen chloride + gold
Equilibrium constant
Construct the equilibrium constant, K, expression for: H_2O_2 + AuCl_3 ⟶ O_2 + HCl + Au 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: 3 H_2O_2 + 2 AuCl_3 ⟶ 3 O_2 + 6 HCl + 2 Au 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 H_2O_2 | 3 | -3 AuCl_3 | 2 | -2 O_2 | 3 | 3 HCl | 6 | 6 Au | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2O_2 | 3 | -3 | ([H2O2])^(-3) AuCl_3 | 2 | -2 | ([AuCl3])^(-2) O_2 | 3 | 3 | ([O2])^3 HCl | 6 | 6 | ([HCl])^6 Au | 2 | 2 | ([Au])^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 = ([H2O2])^(-3) ([AuCl3])^(-2) ([O2])^3 ([HCl])^6 ([Au])^2 = (([O2])^3 ([HCl])^6 ([Au])^2)/(([H2O2])^3 ([AuCl3])^2)
Rate of reaction
Construct the rate of reaction expression for: H_2O_2 + AuCl_3 ⟶ O_2 + HCl + Au 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: 3 H_2O_2 + 2 AuCl_3 ⟶ 3 O_2 + 6 HCl + 2 Au 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 H_2O_2 | 3 | -3 AuCl_3 | 2 | -2 O_2 | 3 | 3 HCl | 6 | 6 Au | 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 H_2O_2 | 3 | -3 | -1/3 (Δ[H2O2])/(Δt) AuCl_3 | 2 | -2 | -1/2 (Δ[AuCl3])/(Δt) O_2 | 3 | 3 | 1/3 (Δ[O2])/(Δt) HCl | 6 | 6 | 1/6 (Δ[HCl])/(Δt) Au | 2 | 2 | 1/2 (Δ[Au])/(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 = -1/3 (Δ[H2O2])/(Δt) = -1/2 (Δ[AuCl3])/(Δt) = 1/3 (Δ[O2])/(Δt) = 1/6 (Δ[HCl])/(Δt) = 1/2 (Δ[Au])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| hydrogen peroxide | gold(III) chloride | oxygen | hydrogen chloride | gold formula | H_2O_2 | AuCl_3 | O_2 | HCl | Au Hill formula | H_2O_2 | AuCl_3 | O_2 | ClH | Au name | hydrogen peroxide | gold(III) chloride | oxygen | hydrogen chloride | gold IUPAC name | hydrogen peroxide | trichlorogold | molecular oxygen | hydrogen chloride | gold
Substance properties
| hydrogen peroxide | gold(III) chloride | oxygen | hydrogen chloride | gold molar mass | 34.014 g/mol | 303.3 g/mol | 31.998 g/mol | 36.46 g/mol | 196.966569 g/mol phase | liquid (at STP) | | gas (at STP) | gas (at STP) | solid (at STP) melting point | -0.43 °C | | -218 °C | -114.17 °C | 1063 °C boiling point | 150.2 °C | | -183 °C | -85 °C | 2856 °C density | 1.44 g/cm^3 | | 0.001429 g/cm^3 (at 0 °C) | 0.00149 g/cm^3 (at 25 °C) | 19.3 g/cm^3 solubility in water | miscible | | | miscible | insoluble surface tension | 0.0804 N/m | | 0.01347 N/m | | dynamic viscosity | 0.001249 Pa s (at 20 °C) | | 2.055×10^-5 Pa s (at 25 °C) | | odor | | | odorless | |
Units