HF + HCCl3 = HCl + HCF2Cl

HF hydrogen fluoride + HCCl3 ⟶ HCl hydrogen chloride + HCF2Cl

Balance the chemical equation algebraically: HF + HCCl3 ⟶ HCl + HCF2Cl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HF + c_2 HCCl3 ⟶ c_3 HCl + c_4 HCF2Cl Set the number of atoms in the reactants equal to the number of atoms in the products for F, H, C and Cl: F: | c_1 = 2 c_4 H: | c_1 + c_2 = c_3 + c_4 C: | c_2 = c_4 Cl: | 3 c_2 = c_3 + 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 = 2 c_2 = 1 c_3 = 2 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 2 HF + HCCl3 ⟶ 2 HCl + HCF2Cl

+ HCCl3 ⟶ + HCF2Cl

hydrogen fluoride + HCCl3 ⟶ hydrogen chloride + HCF2Cl

Construct the equilibrium constant, K, expression for: HF + HCCl3 ⟶ HCl + HCF2Cl 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 HF + HCCl3 ⟶ 2 HCl + HCF2Cl 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 HF | 2 | -2 HCCl3 | 1 | -1 HCl | 2 | 2 HCF2Cl | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HF | 2 | -2 | ([HF])^(-2) HCCl3 | 1 | -1 | ([HCCl3])^(-1) HCl | 2 | 2 | ([HCl])^2 HCF2Cl | 1 | 1 | [HCF2Cl] 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 = ([HF])^(-2) ([HCCl3])^(-1) ([HCl])^2 [HCF2Cl] = (([HCl])^2 [HCF2Cl])/(([HF])^2 [HCCl3])

Construct the rate of reaction expression for: HF + HCCl3 ⟶ HCl + HCF2Cl 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 HF + HCCl3 ⟶ 2 HCl + HCF2Cl 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 HF | 2 | -2 HCCl3 | 1 | -1 HCl | 2 | 2 HCF2Cl | 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 HF | 2 | -2 | -1/2 (Δ[HF])/(Δt) HCCl3 | 1 | -1 | -(Δ[HCCl3])/(Δt) HCl | 2 | 2 | 1/2 (Δ[HCl])/(Δt) HCF2Cl | 1 | 1 | (Δ[HCF2Cl])/(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[HF])/(Δt) = -(Δ[HCCl3])/(Δt) = 1/2 (Δ[HCl])/(Δt) = (Δ[HCF2Cl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen fluoride | HCCl3 | hydrogen chloride | HCF2Cl formula | HF | HCCl3 | HCl | HCF2Cl Hill formula | FH | CHCl3 | ClH | CHClF2 name | hydrogen fluoride | | hydrogen chloride |

| hydrogen fluoride | HCCl3 | hydrogen chloride | HCF2Cl molar mass | 20.006 g/mol | 119.4 g/mol | 36.46 g/mol | 86.47 g/mol phase | gas (at STP) | | gas (at STP) | melting point | -83.36 °C | | -114.17 °C | boiling point | 19.5 °C | | -85 °C | density | 8.18×10^-4 g/cm^3 (at 25 °C) | | 0.00149 g/cm^3 (at 25 °C) | solubility in water | miscible | | miscible | dynamic viscosity | 1.2571×10^-5 Pa s (at 20 °C) | | |