H2O + KCl = O2 + HCl + KH

H_2O water + KCl potassium chloride ⟶ O_2 oxygen + HCl hydrogen chloride + KH potassium hydride

Balance the chemical equation algebraically: H_2O + KCl ⟶ O_2 + HCl + KH Add stoichiometric coefficients, c_i, to the reactants and products: c_1 H_2O + c_2 KCl ⟶ c_3 O_2 + c_4 HCl + c_5 KH Set the number of atoms in the reactants equal to the number of atoms in the products for H, O, Cl and K: H: | 2 c_1 = c_4 + c_5 O: | c_1 = 2 c_3 Cl: | c_2 = c_4 K: | c_2 = 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_3 = 1 and solve the system of equations for the remaining coefficients: c_1 = 2 c_2 = 2 c_3 = 1 c_4 = 2 c_5 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 H_2O + 2 KCl ⟶ O_2 + 2 HCl + 2 KH

+ ⟶ + +

water + potassium chloride ⟶ oxygen + hydrogen chloride + potassium hydride

Construct the equilibrium constant, K, expression for: H_2O + KCl ⟶ O_2 + HCl + KH 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 H_2O + 2 KCl ⟶ O_2 + 2 HCl + 2 KH 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 | 2 | -2 KCl | 2 | -2 O_2 | 1 | 1 HCl | 2 | 2 KH | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression H_2O | 2 | -2 | ([H2O])^(-2) KCl | 2 | -2 | ([KCl])^(-2) O_2 | 1 | 1 | [O2] HCl | 2 | 2 | ([HCl])^2 KH | 2 | 2 | ([KH])^2 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])^(-2) ([KCl])^(-2) [O2] ([HCl])^2 ([KH])^2 = ([O2] ([HCl])^2 ([KH])^2)/(([H2O])^2 ([KCl])^2)

Construct the rate of reaction expression for: H_2O + KCl ⟶ O_2 + HCl + KH 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 H_2O + 2 KCl ⟶ O_2 + 2 HCl + 2 KH 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 | 2 | -2 KCl | 2 | -2 O_2 | 1 | 1 HCl | 2 | 2 KH | 2 | 2 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 | 2 | -2 | -1/2 (Δ[H2O])/(Δt) KCl | 2 | -2 | -1/2 (Δ[KCl])/(Δt) O_2 | 1 | 1 | (Δ[O2])/(Δt) HCl | 2 | 2 | 1/2 (Δ[HCl])/(Δt) KH | 2 | 2 | 1/2 (Δ[KH])/(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[H2O])/(Δt) = -1/2 (Δ[KCl])/(Δt) = (Δ[O2])/(Δt) = 1/2 (Δ[HCl])/(Δt) = 1/2 (Δ[KH])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| water | potassium chloride | oxygen | hydrogen chloride | potassium hydride formula | H_2O | KCl | O_2 | HCl | KH Hill formula | H_2O | ClK | O_2 | ClH | HK name | water | potassium chloride | oxygen | hydrogen chloride | potassium hydride IUPAC name | water | potassium chloride | molecular oxygen | hydrogen chloride | potassium hydride

| water | potassium chloride | oxygen | hydrogen chloride | potassium hydride molar mass | 18.015 g/mol | 74.55 g/mol | 31.998 g/mol | 36.46 g/mol | 40.106 g/mol phase | liquid (at STP) | solid (at STP) | gas (at STP) | gas (at STP) | liquid (at STP) melting point | 0 °C | 770 °C | -218 °C | -114.17 °C | boiling point | 99.9839 °C | 1420 °C | -183 °C | -85 °C | 316 °C density | 1 g/cm^3 | 1.98 g/cm^3 | 0.001429 g/cm^3 (at 0 °C) | 0.00149 g/cm^3 (at 25 °C) | 1.47 g/cm^3 solubility in water | | soluble | | miscible | surface tension | 0.0728 N/m | | 0.01347 N/m | | dynamic viscosity | 8.9×10^-4 Pa s (at 25 °C) | | 2.055×10^-5 Pa s (at 25 °C) | | odor | odorless | odorless | odorless | |