HIO3 + H2SO3 = H2SO4 + HI

HIO_3 (iodic acid) + H_2SO_3 (sulfurous acid) ⟶ H_2SO_4 (sulfuric acid) + HI (hydrogen iodide)

Balance the chemical equation algebraically: HIO_3 + H_2SO_3 ⟶ H_2SO_4 + HI Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HIO_3 + c_2 H_2SO_3 ⟶ c_3 H_2SO_4 + c_4 HI Set the number of atoms in the reactants equal to the number of atoms in the products for H, I, O and S: H: | c_1 + 2 c_2 = 2 c_3 + c_4 I: | c_1 = c_4 O: | 3 c_1 + 3 c_2 = 4 c_3 S: | 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 3 c_3 = 3 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | HIO_3 + 3 H_2SO_3 ⟶ 3 H_2SO_4 + HI

+ ⟶ +

iodic acid + sulfurous acid ⟶ sulfuric acid + hydrogen iodide

Construct the equilibrium constant, K, expression for: HIO_3 + H_2SO_3 ⟶ H_2SO_4 + HI 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: HIO_3 + 3 H_2SO_3 ⟶ 3 H_2SO_4 + HI 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 HIO_3 | 1 | -1 H_2SO_3 | 3 | -3 H_2SO_4 | 3 | 3 HI | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HIO_3 | 1 | -1 | ([HIO3])^(-1) H_2SO_3 | 3 | -3 | ([H2SO3])^(-3) H_2SO_4 | 3 | 3 | ([H2SO4])^3 HI | 1 | 1 | [HI] 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 = ([HIO3])^(-1) ([H2SO3])^(-3) ([H2SO4])^3 [HI] = (([H2SO4])^3 [HI])/([HIO3] ([H2SO3])^3)

Construct the rate of reaction expression for: HIO_3 + H_2SO_3 ⟶ H_2SO_4 + HI 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: HIO_3 + 3 H_2SO_3 ⟶ 3 H_2SO_4 + HI 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 HIO_3 | 1 | -1 H_2SO_3 | 3 | -3 H_2SO_4 | 3 | 3 HI | 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 HIO_3 | 1 | -1 | -(Δ[HIO3])/(Δt) H_2SO_3 | 3 | -3 | -1/3 (Δ[H2SO3])/(Δt) H_2SO_4 | 3 | 3 | 1/3 (Δ[H2SO4])/(Δt) HI | 1 | 1 | (Δ[HI])/(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[HIO3])/(Δt) = -1/3 (Δ[H2SO3])/(Δt) = 1/3 (Δ[H2SO4])/(Δt) = (Δ[HI])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| iodic acid | sulfurous acid | sulfuric acid | hydrogen iodide formula | HIO_3 | H_2SO_3 | H_2SO_4 | HI Hill formula | HIO_3 | H_2O_3S | H_2O_4S | HI name | iodic acid | sulfurous acid | sulfuric acid | hydrogen iodide

| iodic acid | sulfurous acid | sulfuric acid | hydrogen iodide molar mass | 175.91 g/mol | 82.07 g/mol | 98.07 g/mol | 127.912 g/mol phase | solid (at STP) | | liquid (at STP) | gas (at STP) melting point | 110 °C | | 10.371 °C | -50.76 °C boiling point | | | 279.6 °C | -35.55 °C density | 4.629 g/cm^3 | 1.03 g/cm^3 | 1.8305 g/cm^3 | 0.005228 g/cm^3 (at 25 °C) solubility in water | very soluble | very soluble | very soluble | very soluble surface tension | | | 0.0735 N/m | dynamic viscosity | | | 0.021 Pa s (at 25 °C) | 0.001321 Pa s (at -39 °C) odor | | | odorless |