Input interpretation
H_2SO_4 sulfuric acid + KI potassium iodide + PbO_2 lead dioxide ⟶ H_2O water + K_2SO_4 potassium sulfate + I_2 iodine + PbSO_4 lead(II) sulfate
Balanced equation
Balance the chemical equation algebraically: H_2SO_4 + KI + PbO_2 ⟶ H_2O + K_2SO_4 + I_2 + PbSO_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2SO_4 + c_2 KI + c_3 PbO_2 ⟶ c_4 H_2O + c_5 K_2SO_4 + c_6 I_2 + c_7 PbSO_4 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, S, I, K and Pb: H: | 2 c_1 = 2 c_4 O: | 4 c_1 + 2 c_3 = c_4 + 4 c_5 + 4 c_7 S: | c_1 = c_5 + c_7 I: | c_2 = 2 c_6 K: | c_2 = 2 c_5 Pb: | c_3 = c_7 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_3 = 1 and solve the system of equations for the remaining coefficients: c_1 = 2 c_2 = 2 c_3 = 1 c_4 = 2 c_5 = 1 c_6 = 1 c_7 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 H_2SO_4 + 2 KI + PbO_2 ⟶ 2 H_2O + K_2SO_4 + I_2 + PbSO_4
Structures
+ + ⟶ + + +
Names
sulfuric acid + potassium iodide + lead dioxide ⟶ water + potassium sulfate + iodine + lead(II) sulfate
Equilibrium constant
![Construct the equilibrium constant, K, expression for: H_2SO_4 + KI + PbO_2 ⟶ H_2O + K_2SO_4 + I_2 + PbSO_4 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 H_2SO_4 + 2 KI + PbO_2 ⟶ 2 H_2O + K_2SO_4 + I_2 + PbSO_4 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_2SO_4 | 2 | -2 KI | 2 | -2 PbO_2 | 1 | -1 H_2O | 2 | 2 K_2SO_4 | 1 | 1 I_2 | 1 | 1 PbSO_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2SO_4 | 2 | -2 | ([H2SO4])^(-2) KI | 2 | -2 | ([KI])^(-2) PbO_2 | 1 | -1 | ([PbO2])^(-1) H_2O | 2 | 2 | ([H2O])^2 K_2SO_4 | 1 | 1 | [K2SO4] I_2 | 1 | 1 | [I2] PbSO_4 | 1 | 1 | [PbSO4] 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 = ([H2SO4])^(-2) ([KI])^(-2) ([PbO2])^(-1) ([H2O])^2 [K2SO4] [I2] [PbSO4] = (([H2O])^2 [K2SO4] [I2] [PbSO4])/(([H2SO4])^2 ([KI])^2 [PbO2])](../image_source/e6abc7d927ed2bf74f03e9ffb2ee1945.png)
Construct the equilibrium constant, K, expression for: H_2SO_4 + KI + PbO_2 ⟶ H_2O + K_2SO_4 + I_2 + PbSO_4 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 H_2SO_4 + 2 KI + PbO_2 ⟶ 2 H_2O + K_2SO_4 + I_2 + PbSO_4 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_2SO_4 | 2 | -2 KI | 2 | -2 PbO_2 | 1 | -1 H_2O | 2 | 2 K_2SO_4 | 1 | 1 I_2 | 1 | 1 PbSO_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2SO_4 | 2 | -2 | ([H2SO4])^(-2) KI | 2 | -2 | ([KI])^(-2) PbO_2 | 1 | -1 | ([PbO2])^(-1) H_2O | 2 | 2 | ([H2O])^2 K_2SO_4 | 1 | 1 | [K2SO4] I_2 | 1 | 1 | [I2] PbSO_4 | 1 | 1 | [PbSO4] 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 = ([H2SO4])^(-2) ([KI])^(-2) ([PbO2])^(-1) ([H2O])^2 [K2SO4] [I2] [PbSO4] = (([H2O])^2 [K2SO4] [I2] [PbSO4])/(([H2SO4])^2 ([KI])^2 [PbO2])
Rate of reaction
![Construct the rate of reaction expression for: H_2SO_4 + KI + PbO_2 ⟶ H_2O + K_2SO_4 + I_2 + PbSO_4 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 H_2SO_4 + 2 KI + PbO_2 ⟶ 2 H_2O + K_2SO_4 + I_2 + PbSO_4 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_2SO_4 | 2 | -2 KI | 2 | -2 PbO_2 | 1 | -1 H_2O | 2 | 2 K_2SO_4 | 1 | 1 I_2 | 1 | 1 PbSO_4 | 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 H_2SO_4 | 2 | -2 | -1/2 (Δ[H2SO4])/(Δt) KI | 2 | -2 | -1/2 (Δ[KI])/(Δt) PbO_2 | 1 | -1 | -(Δ[PbO2])/(Δt) H_2O | 2 | 2 | 1/2 (Δ[H2O])/(Δt) K_2SO_4 | 1 | 1 | (Δ[K2SO4])/(Δt) I_2 | 1 | 1 | (Δ[I2])/(Δt) PbSO_4 | 1 | 1 | (Δ[PbSO4])/(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[H2SO4])/(Δt) = -1/2 (Δ[KI])/(Δt) = -(Δ[PbO2])/(Δt) = 1/2 (Δ[H2O])/(Δt) = (Δ[K2SO4])/(Δt) = (Δ[I2])/(Δt) = (Δ[PbSO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)](../image_source/5ec7d5a011f2caf6c2d42de79310954b.png)
Construct the rate of reaction expression for: H_2SO_4 + KI + PbO_2 ⟶ H_2O + K_2SO_4 + I_2 + PbSO_4 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 H_2SO_4 + 2 KI + PbO_2 ⟶ 2 H_2O + K_2SO_4 + I_2 + PbSO_4 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_2SO_4 | 2 | -2 KI | 2 | -2 PbO_2 | 1 | -1 H_2O | 2 | 2 K_2SO_4 | 1 | 1 I_2 | 1 | 1 PbSO_4 | 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 H_2SO_4 | 2 | -2 | -1/2 (Δ[H2SO4])/(Δt) KI | 2 | -2 | -1/2 (Δ[KI])/(Δt) PbO_2 | 1 | -1 | -(Δ[PbO2])/(Δt) H_2O | 2 | 2 | 1/2 (Δ[H2O])/(Δt) K_2SO_4 | 1 | 1 | (Δ[K2SO4])/(Δt) I_2 | 1 | 1 | (Δ[I2])/(Δt) PbSO_4 | 1 | 1 | (Δ[PbSO4])/(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[H2SO4])/(Δt) = -1/2 (Δ[KI])/(Δt) = -(Δ[PbO2])/(Δt) = 1/2 (Δ[H2O])/(Δt) = (Δ[K2SO4])/(Δt) = (Δ[I2])/(Δt) = (Δ[PbSO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| sulfuric acid | potassium iodide | lead dioxide | water | potassium sulfate | iodine | lead(II) sulfate formula | H_2SO_4 | KI | PbO_2 | H_2O | K_2SO_4 | I_2 | PbSO_4 Hill formula | H_2O_4S | IK | O_2Pb | H_2O | K_2O_4S | I_2 | O_4PbS name | sulfuric acid | potassium iodide | lead dioxide | water | potassium sulfate | iodine | lead(II) sulfate IUPAC name | sulfuric acid | potassium iodide | | water | dipotassium sulfate | molecular iodine |