H2O + KClO2 = H2 + KClO3

H_2O water + KClO2 ⟶ H_2 hydrogen + KClO_3 potassium chlorate

Balance the chemical equation algebraically: H_2O + KClO2 ⟶ H_2 + KClO_3 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2O + c_2 KClO2 ⟶ c_3 H_2 + c_4 KClO_3 Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, K and Cl: H: | 2 c_1 = 2 c_3 O: | c_1 + 2 c_2 = 3 c_4 K: | c_2 = c_4 Cl: | c_2 = c_4 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 = 1 c_3 = 1 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | H_2O + KClO2 ⟶ H_2 + KClO_3

+ KClO2 ⟶ +

water + KClO2 ⟶ hydrogen + potassium chlorate

Construct the equilibrium constant, K, expression for: H_2O + KClO2 ⟶ H_2 + 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: H_2O + KClO2 ⟶ H_2 + 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 H_2O | 1 | -1 KClO2 | 1 | -1 H_2 | 1 | 1 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 H_2O | 1 | -1 | ([H2O])^(-1) KClO2 | 1 | -1 | ([KClO2])^(-1) H_2 | 1 | 1 | [H2] 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 = ([H2O])^(-1) ([KClO2])^(-1) [H2] [KClO3] = ([H2] [KClO3])/([H2O] [KClO2])

Construct the rate of reaction expression for: H_2O + KClO2 ⟶ H_2 + 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: H_2O + KClO2 ⟶ H_2 + 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 H_2O | 1 | -1 KClO2 | 1 | -1 H_2 | 1 | 1 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 H_2O | 1 | -1 | -(Δ[H2O])/(Δt) KClO2 | 1 | -1 | -(Δ[KClO2])/(Δt) H_2 | 1 | 1 | (Δ[H2])/(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 = -(Δ[H2O])/(Δt) = -(Δ[KClO2])/(Δt) = (Δ[H2])/(Δt) = (Δ[KClO3])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| water | KClO2 | hydrogen | potassium chlorate formula | H_2O | KClO2 | H_2 | KClO_3 Hill formula | H_2O | ClKO2 | H_2 | ClKO_3 name | water | | hydrogen | potassium chlorate IUPAC name | water | | molecular hydrogen | potassium chlorate

| water | KClO2 | hydrogen | potassium chlorate molar mass | 18.015 g/mol | 106.5 g/mol | 2.016 g/mol | 122.5 g/mol phase | liquid (at STP) | | gas (at STP) | solid (at STP) melting point | 0 °C | | -259.2 °C | 356 °C boiling point | 99.9839 °C | | -252.8 °C | density | 1 g/cm^3 | | 8.99×10^-5 g/cm^3 (at 0 °C) | 2.34 g/cm^3 solubility in water | | | | soluble surface tension | 0.0728 N/m | | | dynamic viscosity | 8.9×10^-4 Pa s (at 25 °C) | | 8.9×10^-6 Pa s (at 25 °C) | odor | odorless | | odorless |