HCl + Pb = H2 + PbCl4

HCl hydrogen chloride + Pb lead ⟶ H_2 hydrogen + Cl_4Pb lead tetrachloride

Balance the chemical equation algebraically: HCl + Pb ⟶ H_2 + Cl_4Pb Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HCl + c_2 Pb ⟶ c_3 H_2 + c_4 Cl_4Pb Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, H and Pb: Cl: | c_1 = 4 c_4 H: | c_1 = 2 c_3 Pb: | 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_2 = 1 and solve the system of equations for the remaining coefficients: c_1 = 4 c_2 = 1 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 4 HCl + Pb ⟶ 2 H_2 + Cl_4Pb

+ ⟶ +

hydrogen chloride + lead ⟶ hydrogen + lead tetrachloride

Construct the equilibrium constant, K, expression for: HCl + Pb ⟶ H_2 + Cl_4Pb 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: 4 HCl + Pb ⟶ 2 H_2 + Cl_4Pb 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 HCl | 4 | -4 Pb | 1 | -1 H_2 | 2 | 2 Cl_4Pb | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HCl | 4 | -4 | ([HCl])^(-4) Pb | 1 | -1 | ([Pb])^(-1) H_2 | 2 | 2 | ([H2])^2 Cl_4Pb | 1 | 1 | [Cl4Pb] 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 = ([HCl])^(-4) ([Pb])^(-1) ([H2])^2 [Cl4Pb] = (([H2])^2 [Cl4Pb])/(([HCl])^4 [Pb])

Construct the rate of reaction expression for: HCl + Pb ⟶ H_2 + Cl_4Pb 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: 4 HCl + Pb ⟶ 2 H_2 + Cl_4Pb 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 HCl | 4 | -4 Pb | 1 | -1 H_2 | 2 | 2 Cl_4Pb | 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 HCl | 4 | -4 | -1/4 (Δ[HCl])/(Δt) Pb | 1 | -1 | -(Δ[Pb])/(Δt) H_2 | 2 | 2 | 1/2 (Δ[H2])/(Δt) Cl_4Pb | 1 | 1 | (Δ[Cl4Pb])/(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 = -1/4 (Δ[HCl])/(Δt) = -(Δ[Pb])/(Δt) = 1/2 (Δ[H2])/(Δt) = (Δ[Cl4Pb])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen chloride | lead | hydrogen | lead tetrachloride formula | HCl | Pb | H_2 | Cl_4Pb Hill formula | ClH | Pb | H_2 | Cl_4Pb name | hydrogen chloride | lead | hydrogen | lead tetrachloride IUPAC name | hydrogen chloride | lead | molecular hydrogen | tetrachloroplumbane

| hydrogen chloride | lead | hydrogen | lead tetrachloride molar mass | 36.46 g/mol | 207.2 g/mol | 2.016 g/mol | 349 g/mol phase | gas (at STP) | solid (at STP) | gas (at STP) | liquid (at STP) melting point | -114.17 °C | 327.4 °C | -259.2 °C | -15 °C boiling point | -85 °C | 1740 °C | -252.8 °C | density | 0.00149 g/cm^3 (at 25 °C) | 11.34 g/cm^3 | 8.99×10^-5 g/cm^3 (at 0 °C) | 3.18 g/cm^3 solubility in water | miscible | insoluble | | dynamic viscosity | | 0.00183 Pa s (at 38 °C) | 8.9×10^-6 Pa s (at 25 °C) | odor | | | odorless |