Input interpretation
KOH potassium hydroxide + Br_2 bromine + SbO2 ⟶ H_2O water + KBr potassium bromide + K3SbO4
Balanced equation
Balance the chemical equation algebraically: KOH + Br_2 + SbO2 ⟶ H_2O + KBr + K3SbO4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 KOH + c_2 Br_2 + c_3 SbO2 ⟶ c_4 H_2O + c_5 KBr + c_6 K3SbO4 Set the number of atoms in the reactants equal to the number of atoms in the products for H, K, O, Br and Sb: H: | c_1 = 2 c_4 K: | c_1 = c_5 + 3 c_6 O: | c_1 + 2 c_3 = c_4 + 4 c_6 Br: | 2 c_2 = c_5 Sb: | c_3 = c_6 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 = 8 c_2 = 1 c_3 = 2 c_4 = 4 c_5 = 2 c_6 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 8 KOH + Br_2 + 2 SbO2 ⟶ 4 H_2O + 2 KBr + 2 K3SbO4
Structures
+ + SbO2 ⟶ + + K3SbO4
Names
potassium hydroxide + bromine + SbO2 ⟶ water + potassium bromide + K3SbO4
Equilibrium constant
Construct the equilibrium constant, K, expression for: KOH + Br_2 + SbO2 ⟶ H_2O + KBr + K3SbO4 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: 8 KOH + Br_2 + 2 SbO2 ⟶ 4 H_2O + 2 KBr + 2 K3SbO4 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 KOH | 8 | -8 Br_2 | 1 | -1 SbO2 | 2 | -2 H_2O | 4 | 4 KBr | 2 | 2 K3SbO4 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression KOH | 8 | -8 | ([KOH])^(-8) Br_2 | 1 | -1 | ([Br2])^(-1) SbO2 | 2 | -2 | ([SbO2])^(-2) H_2O | 4 | 4 | ([H2O])^4 KBr | 2 | 2 | ([KBr])^2 K3SbO4 | 2 | 2 | ([K3SbO4])^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 = ([KOH])^(-8) ([Br2])^(-1) ([SbO2])^(-2) ([H2O])^4 ([KBr])^2 ([K3SbO4])^2 = (([H2O])^4 ([KBr])^2 ([K3SbO4])^2)/(([KOH])^8 [Br2] ([SbO2])^2)
Rate of reaction
Construct the rate of reaction expression for: KOH + Br_2 + SbO2 ⟶ H_2O + KBr + K3SbO4 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: 8 KOH + Br_2 + 2 SbO2 ⟶ 4 H_2O + 2 KBr + 2 K3SbO4 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 KOH | 8 | -8 Br_2 | 1 | -1 SbO2 | 2 | -2 H_2O | 4 | 4 KBr | 2 | 2 K3SbO4 | 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 KOH | 8 | -8 | -1/8 (Δ[KOH])/(Δt) Br_2 | 1 | -1 | -(Δ[Br2])/(Δt) SbO2 | 2 | -2 | -1/2 (Δ[SbO2])/(Δt) H_2O | 4 | 4 | 1/4 (Δ[H2O])/(Δt) KBr | 2 | 2 | 1/2 (Δ[KBr])/(Δt) K3SbO4 | 2 | 2 | 1/2 (Δ[K3SbO4])/(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 = -1/8 (Δ[KOH])/(Δt) = -(Δ[Br2])/(Δt) = -1/2 (Δ[SbO2])/(Δt) = 1/4 (Δ[H2O])/(Δt) = 1/2 (Δ[KBr])/(Δt) = 1/2 (Δ[K3SbO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| potassium hydroxide | bromine | SbO2 | water | potassium bromide | K3SbO4 formula | KOH | Br_2 | SbO2 | H_2O | KBr | K3SbO4 Hill formula | HKO | Br_2 | O2Sb | H_2O | BrK | K3O4Sb name | potassium hydroxide | bromine | | water | potassium bromide | IUPAC name | potassium hydroxide | molecular bromine | | water | potassium bromide |
Substance properties
| potassium hydroxide | bromine | SbO2 | water | potassium bromide | K3SbO4 molar mass | 56.105 g/mol | 159.81 g/mol | 153.758 g/mol | 18.015 g/mol | 119 g/mol | 303.051 g/mol phase | solid (at STP) | liquid (at STP) | | liquid (at STP) | solid (at STP) | melting point | 406 °C | -7.2 °C | | 0 °C | 734 °C | boiling point | 1327 °C | 58.8 °C | | 99.9839 °C | 1435 °C | density | 2.044 g/cm^3 | 3.119 g/cm^3 | | 1 g/cm^3 | 2.75 g/cm^3 | solubility in water | soluble | insoluble | | | soluble | surface tension | | 0.0409 N/m | | 0.0728 N/m | | dynamic viscosity | 0.001 Pa s (at 550 °C) | 9.44×10^-4 Pa s (at 25 °C) | | 8.9×10^-4 Pa s (at 25 °C) | | odor | | | | odorless | |
Units