KIO3 + BaCl2 = KCl + Ba(IO3)2

KIO_3 potassium iodate + BaCl_2 barium chloride ⟶ KCl potassium chloride + BaI_2O_6 barium iodate

Balance the chemical equation algebraically: KIO_3 + BaCl_2 ⟶ KCl + BaI_2O_6 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 KIO_3 + c_2 BaCl_2 ⟶ c_3 KCl + c_4 BaI_2O_6 Set the number of atoms in the reactants equal to the number of atoms in the products for I, K, O, Ba and Cl: I: | c_1 = 2 c_4 K: | c_1 = c_3 O: | 3 c_1 = 6 c_4 Ba: | c_2 = c_4 Cl: | 2 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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 2 c_2 = 1 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 KIO_3 + BaCl_2 ⟶ 2 KCl + BaI_2O_6

+ ⟶ +

potassium iodate + barium chloride ⟶ potassium chloride + barium iodate

Construct the equilibrium constant, K, expression for: KIO_3 + BaCl_2 ⟶ KCl + BaI_2O_6 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 KIO_3 + BaCl_2 ⟶ 2 KCl + BaI_2O_6 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 KIO_3 | 2 | -2 BaCl_2 | 1 | -1 KCl | 2 | 2 BaI_2O_6 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression KIO_3 | 2 | -2 | ([KIO3])^(-2) BaCl_2 | 1 | -1 | ([BaCl2])^(-1) KCl | 2 | 2 | ([KCl])^2 BaI_2O_6 | 1 | 1 | [BaI2O6] 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 = ([KIO3])^(-2) ([BaCl2])^(-1) ([KCl])^2 [BaI2O6] = (([KCl])^2 [BaI2O6])/(([KIO3])^2 [BaCl2])

Construct the rate of reaction expression for: KIO_3 + BaCl_2 ⟶ KCl + BaI_2O_6 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 KIO_3 + BaCl_2 ⟶ 2 KCl + BaI_2O_6 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 KIO_3 | 2 | -2 BaCl_2 | 1 | -1 KCl | 2 | 2 BaI_2O_6 | 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 KIO_3 | 2 | -2 | -1/2 (Δ[KIO3])/(Δt) BaCl_2 | 1 | -1 | -(Δ[BaCl2])/(Δt) KCl | 2 | 2 | 1/2 (Δ[KCl])/(Δt) BaI_2O_6 | 1 | 1 | (Δ[BaI2O6])/(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[KIO3])/(Δt) = -(Δ[BaCl2])/(Δt) = 1/2 (Δ[KCl])/(Δt) = (Δ[BaI2O6])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| potassium iodate | barium chloride | potassium chloride | barium iodate formula | KIO_3 | BaCl_2 | KCl | BaI_2O_6 Hill formula | IKO_3 | BaCl_2 | ClK | BaI_2O_6 name | potassium iodate | barium chloride | potassium chloride | barium iodate IUPAC name | potassium iodate | barium(+2) cation dichloride | potassium chloride | barium(+2) cation diiodate

| potassium iodate | barium chloride | potassium chloride | barium iodate molar mass | 214 g/mol | 208.2 g/mol | 74.55 g/mol | 487.13 g/mol phase | solid (at STP) | solid (at STP) | solid (at STP) | melting point | 560 °C | 963 °C | 770 °C | boiling point | | | 1420 °C | density | 1.005 g/cm^3 | 3.856 g/cm^3 | 1.98 g/cm^3 | 4.998 g/cm^3 solubility in water | | | soluble | odor | | odorless | odorless |