HI + SO2Cl2 = H2O + HCl + I2 + H2S

HI hydrogen iodide + SO_2Cl_2 sulfuryl chloride ⟶ H_2O water + HCl hydrogen chloride + I_2 iodine + H_2S hydrogen sulfide

Balance the chemical equation algebraically: HI + SO_2Cl_2 ⟶ H_2O + HCl + I_2 + H_2S Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HI + c_2 SO_2Cl_2 ⟶ c_3 H_2O + c_4 HCl + c_5 I_2 + c_6 H_2S Set the number of atoms in the reactants equal to the number of atoms in the products for H, I, Cl, O and S: H: | c_1 = 2 c_3 + c_4 + 2 c_6 I: | c_1 = 2 c_5 Cl: | 2 c_2 = c_4 O: | 2 c_2 = c_3 S: | c_2 = 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 = 2 c_5 = 4 c_6 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 8 HI + SO_2Cl_2 ⟶ 2 H_2O + 2 HCl + 4 I_2 + H_2S

+ ⟶ + + +

hydrogen iodide + sulfuryl chloride ⟶ water + hydrogen chloride + iodine + hydrogen sulfide

Construct the equilibrium constant, K, expression for: HI + SO_2Cl_2 ⟶ H_2O + HCl + I_2 + H_2S 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 HI + SO_2Cl_2 ⟶ 2 H_2O + 2 HCl + 4 I_2 + H_2S 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 HI | 8 | -8 SO_2Cl_2 | 1 | -1 H_2O | 2 | 2 HCl | 2 | 2 I_2 | 4 | 4 H_2S | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HI | 8 | -8 | ([HI])^(-8) SO_2Cl_2 | 1 | -1 | ([SO2Cl2])^(-1) H_2O | 2 | 2 | ([H2O])^2 HCl | 2 | 2 | ([HCl])^2 I_2 | 4 | 4 | ([I2])^4 H_2S | 1 | 1 | [H2S] 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 = ([HI])^(-8) ([SO2Cl2])^(-1) ([H2O])^2 ([HCl])^2 ([I2])^4 [H2S] = (([H2O])^2 ([HCl])^2 ([I2])^4 [H2S])/(([HI])^8 [SO2Cl2])

Construct the rate of reaction expression for: HI + SO_2Cl_2 ⟶ H_2O + HCl + I_2 + H_2S 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 HI + SO_2Cl_2 ⟶ 2 H_2O + 2 HCl + 4 I_2 + H_2S 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 HI | 8 | -8 SO_2Cl_2 | 1 | -1 H_2O | 2 | 2 HCl | 2 | 2 I_2 | 4 | 4 H_2S | 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 HI | 8 | -8 | -1/8 (Δ[HI])/(Δt) SO_2Cl_2 | 1 | -1 | -(Δ[SO2Cl2])/(Δt) H_2O | 2 | 2 | 1/2 (Δ[H2O])/(Δt) HCl | 2 | 2 | 1/2 (Δ[HCl])/(Δt) I_2 | 4 | 4 | 1/4 (Δ[I2])/(Δt) H_2S | 1 | 1 | (Δ[H2S])/(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[HI])/(Δt) = -(Δ[SO2Cl2])/(Δt) = 1/2 (Δ[H2O])/(Δt) = 1/2 (Δ[HCl])/(Δt) = 1/4 (Δ[I2])/(Δt) = (Δ[H2S])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen iodide | sulfuryl chloride | water | hydrogen chloride | iodine | hydrogen sulfide formula | HI | SO_2Cl_2 | H_2O | HCl | I_2 | H_2S Hill formula | HI | Cl_2O_2S | H_2O | ClH | I_2 | H_2S name | hydrogen iodide | sulfuryl chloride | water | hydrogen chloride | iodine | hydrogen sulfide IUPAC name | hydrogen iodide | sulfuryl chloride | water | hydrogen chloride | molecular iodine | hydrogen sulfide

| hydrogen iodide | sulfuryl chloride | water | hydrogen chloride | iodine | hydrogen sulfide molar mass | 127.912 g/mol | 135 g/mol | 18.015 g/mol | 36.46 g/mol | 253.80894 g/mol | 34.08 g/mol phase | gas (at STP) | liquid (at STP) | liquid (at STP) | gas (at STP) | solid (at STP) | gas (at STP) melting point | -50.76 °C | -54 °C | 0 °C | -114.17 °C | 113 °C | -85 °C boiling point | -35.55 °C | 69 °C | 99.9839 °C | -85 °C | 184 °C | -60 °C density | 0.005228 g/cm^3 (at 25 °C) | 1.665 g/cm^3 | 1 g/cm^3 | 0.00149 g/cm^3 (at 25 °C) | 4.94 g/cm^3 | 0.001393 g/cm^3 (at 25 °C) solubility in water | very soluble | decomposes | | miscible | | surface tension | | | 0.0728 N/m | | | dynamic viscosity | 0.001321 Pa s (at -39 °C) | 7×10^-4 Pa s (at 24 °C) | 8.9×10^-4 Pa s (at 25 °C) | | 0.00227 Pa s (at 116 °C) | 1.239×10^-5 Pa s (at 25 °C) odor | | | odorless | | |