HF + CCl4 = HCl + CF4

HF hydrogen fluoride + CCl_4 carbon tetrachloride ⟶ HCl hydrogen chloride + CF_4 tetrafluoromethane

Balance the chemical equation algebraically: HF + CCl_4 ⟶ HCl + CF_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HF + c_2 CCl_4 ⟶ c_3 HCl + c_4 CF_4 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 = 4 c_4 H: | c_1 = c_3 C: | c_2 = c_4 Cl: | 4 c_2 = c_3 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 = 4 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | 4 HF + CCl_4 ⟶ 4 HCl + CF_4

+ ⟶ +

hydrogen fluoride + carbon tetrachloride ⟶ hydrogen chloride + tetrafluoromethane

Construct the equilibrium constant, K, expression for: HF + CCl_4 ⟶ HCl + CF_4 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 HF + CCl_4 ⟶ 4 HCl + CF_4 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 | 4 | -4 CCl_4 | 1 | -1 HCl | 4 | 4 CF_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HF | 4 | -4 | ([HF])^(-4) CCl_4 | 1 | -1 | ([CCl4])^(-1) HCl | 4 | 4 | ([HCl])^4 CF_4 | 1 | 1 | [CF4] 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])^(-4) ([CCl4])^(-1) ([HCl])^4 [CF4] = (([HCl])^4 [CF4])/(([HF])^4 [CCl4])

Construct the rate of reaction expression for: HF + CCl_4 ⟶ HCl + CF_4 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 HF + CCl_4 ⟶ 4 HCl + CF_4 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 | 4 | -4 CCl_4 | 1 | -1 HCl | 4 | 4 CF_4 | 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 | 4 | -4 | -1/4 (Δ[HF])/(Δt) CCl_4 | 1 | -1 | -(Δ[CCl4])/(Δt) HCl | 4 | 4 | 1/4 (Δ[HCl])/(Δt) CF_4 | 1 | 1 | (Δ[CF4])/(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[HF])/(Δt) = -(Δ[CCl4])/(Δt) = 1/4 (Δ[HCl])/(Δt) = (Δ[CF4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen fluoride | carbon tetrachloride | hydrogen chloride | tetrafluoromethane formula | HF | CCl_4 | HCl | CF_4 Hill formula | FH | CCl_4 | ClH | CF_4 name | hydrogen fluoride | carbon tetrachloride | hydrogen chloride | tetrafluoromethane

| hydrogen fluoride | carbon tetrachloride | hydrogen chloride | tetrafluoromethane molar mass | 20.006 g/mol | 153.8 g/mol | 36.46 g/mol | 88.005 g/mol phase | gas (at STP) | liquid (at STP) | gas (at STP) | gas (at STP) melting point | -83.36 °C | -23 °C | -114.17 °C | -184 °C boiling point | 19.5 °C | 76.5 °C | -85 °C | -130 °C density | 8.18×10^-4 g/cm^3 (at 25 °C) | 1.594 g/cm^3 | 0.00149 g/cm^3 (at 25 °C) | solubility in water | miscible | insoluble | miscible | insoluble surface tension | | 0.0269 N/m | | dynamic viscosity | 1.2571×10^-5 Pa s (at 20 °C) | 9.08×10^-4 Pa s (at 25 °C) | | 1.724×10^-5 Pa s (at 25 °C) odor | | ether-like | |