Cl2 + KOH = H2O + KCl + KClO3

Cl_2 (chlorine) + KOH (potassium hydroxide) ⟶ H_2O (water) + KCl (potassium chloride) + KClO_3 (potassium chlorate)

Balance the chemical equation algebraically: Cl_2 + KOH ⟶ H_2O + KCl + KClO_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cl_2 + c_2 KOH ⟶ c_3 H_2O + c_4 KCl + c_5 KClO_3 Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, H, K and O: Cl: | 2 c_1 = c_4 + c_5 H: | c_2 = 2 c_3 K: | c_2 = c_4 + c_5 O: | c_2 = c_3 + 3 c_5 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_5 = 1 and solve the system of equations for the remaining coefficients: c_1 = 3 c_2 = 6 c_3 = 3 c_4 = 5 c_5 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 3 Cl_2 + 6 KOH ⟶ 3 H_2O + 5 KCl + KClO_3

+ ⟶ + +

chlorine + potassium hydroxide ⟶ water + potassium chloride + potassium chlorate

| chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate molecular enthalpy | 0 kJ/mol | -424.6 kJ/mol | -285.8 kJ/mol | -436.5 kJ/mol | -397.7 kJ/mol total enthalpy | 0 kJ/mol | -2548 kJ/mol | -857.5 kJ/mol | -2183 kJ/mol | -397.7 kJ/mol | H_initial = -2548 kJ/mol | | H_final = -3438 kJ/mol | | ΔH_rxn^0 | -3438 kJ/mol - -2548 kJ/mol = -890.1 kJ/mol (exothermic) | | | |

| chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate molecular free energy | 0 kJ/mol | -379.4 kJ/mol | -237.1 kJ/mol | -408.5 kJ/mol | -296.3 kJ/mol total free energy | 0 kJ/mol | -2276 kJ/mol | -711.3 kJ/mol | -2043 kJ/mol | -296.3 kJ/mol | G_initial = -2276 kJ/mol | | G_final = -3050 kJ/mol | | ΔG_rxn^0 | -3050 kJ/mol - -2276 kJ/mol = -773.7 kJ/mol (exergonic) | | | |

| chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate molecular entropy | 223 J/(mol K) | 79 J/(mol K) | 69.91 J/(mol K) | 83 J/(mol K) | 143 J/(mol K) total entropy | 669 J/(mol K) | 474 J/(mol K) | 209.7 J/(mol K) | 415 J/(mol K) | 143 J/(mol K) | S_initial = 1143 J/(mol K) | | S_final = 767.7 J/(mol K) | | ΔS_rxn^0 | 767.7 J/(mol K) - 1143 J/(mol K) = -375.3 J/(mol K) (exoentropic) | | | |

Construct the equilibrium constant, K, expression for: Cl_2 + KOH ⟶ H_2O + KCl + KClO_3 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: 3 Cl_2 + 6 KOH ⟶ 3 H_2O + 5 KCl + KClO_3 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 Cl_2 | 3 | -3 KOH | 6 | -6 H_2O | 3 | 3 KCl | 5 | 5 KClO_3 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Cl_2 | 3 | -3 | ([Cl2])^(-3) KOH | 6 | -6 | ([KOH])^(-6) H_2O | 3 | 3 | ([H2O])^3 KCl | 5 | 5 | ([KCl])^5 KClO_3 | 1 | 1 | [KClO3] 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 = ([Cl2])^(-3) ([KOH])^(-6) ([H2O])^3 ([KCl])^5 [KClO3] = (([H2O])^3 ([KCl])^5 [KClO3])/(([Cl2])^3 ([KOH])^6)

Construct the rate of reaction expression for: Cl_2 + KOH ⟶ H_2O + KCl + KClO_3 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: 3 Cl_2 + 6 KOH ⟶ 3 H_2O + 5 KCl + KClO_3 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 Cl_2 | 3 | -3 KOH | 6 | -6 H_2O | 3 | 3 KCl | 5 | 5 KClO_3 | 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 Cl_2 | 3 | -3 | -1/3 (Δ[Cl2])/(Δt) KOH | 6 | -6 | -1/6 (Δ[KOH])/(Δt) H_2O | 3 | 3 | 1/3 (Δ[H2O])/(Δt) KCl | 5 | 5 | 1/5 (Δ[KCl])/(Δt) KClO_3 | 1 | 1 | (Δ[KClO3])/(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 = -1/3 (Δ[Cl2])/(Δt) = -1/6 (Δ[KOH])/(Δt) = 1/3 (Δ[H2O])/(Δt) = 1/5 (Δ[KCl])/(Δt) = (Δ[KClO3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate formula | Cl_2 | KOH | H_2O | KCl | KClO_3 Hill formula | Cl_2 | HKO | H_2O | ClK | ClKO_3 name | chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate IUPAC name | molecular chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate

| chlorine | potassium hydroxide | water | potassium chloride | potassium chlorate molar mass | 70.9 g/mol | 56.105 g/mol | 18.015 g/mol | 74.55 g/mol | 122.5 g/mol phase | gas (at STP) | solid (at STP) | liquid (at STP) | solid (at STP) | solid (at STP) melting point | -101 °C | 406 °C | 0 °C | 770 °C | 356 °C boiling point | -34 °C | 1327 °C | 99.9839 °C | 1420 °C | density | 0.003214 g/cm^3 (at 0 °C) | 2.044 g/cm^3 | 1 g/cm^3 | 1.98 g/cm^3 | 2.34 g/cm^3 solubility in water | | soluble | | soluble | soluble surface tension | | | 0.0728 N/m | | dynamic viscosity | | 0.001 Pa s (at 550 °C) | 8.9×10^-4 Pa s (at 25 °C) | | odor | | | odorless | odorless |