HCl + C2H4 = C2H5Cl

HCl hydrogen chloride + CH_2=CH_2 ethylene ⟶ C_2H_5Cl chloroethane

Balance the chemical equation algebraically: HCl + CH_2=CH_2 ⟶ C_2H_5Cl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 HCl + c_2 CH_2=CH_2 ⟶ c_3 C_2H_5Cl Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, H and C: Cl: | c_1 = c_3 H: | c_1 + 4 c_2 = 5 c_3 C: | 2 c_2 = 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 1 c_3 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | HCl + CH_2=CH_2 ⟶ C_2H_5Cl

+ ⟶

hydrogen chloride + ethylene ⟶ chloroethane

Construct the equilibrium constant, K, expression for: HCl + CH_2=CH_2 ⟶ C_2H_5Cl 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: HCl + CH_2=CH_2 ⟶ C_2H_5Cl 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 | 1 | -1 CH_2=CH_2 | 1 | -1 C_2H_5Cl | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression HCl | 1 | -1 | ([HCl])^(-1) CH_2=CH_2 | 1 | -1 | ([CH2=CH2])^(-1) C_2H_5Cl | 1 | 1 | [C2H5Cl] 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])^(-1) ([CH2=CH2])^(-1) [C2H5Cl] = ([C2H5Cl])/([HCl] [CH2=CH2])

Construct the rate of reaction expression for: HCl + CH_2=CH_2 ⟶ C_2H_5Cl 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: HCl + CH_2=CH_2 ⟶ C_2H_5Cl 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 | 1 | -1 CH_2=CH_2 | 1 | -1 C_2H_5Cl | 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 | 1 | -1 | -(Δ[HCl])/(Δt) CH_2=CH_2 | 1 | -1 | -(Δ[CH2=CH2])/(Δt) C_2H_5Cl | 1 | 1 | (Δ[C2H5Cl])/(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[HCl])/(Δt) = -(Δ[CH2=CH2])/(Δt) = (Δ[C2H5Cl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| hydrogen chloride | ethylene | chloroethane formula | HCl | CH_2=CH_2 | C_2H_5Cl Hill formula | ClH | C_2H_4 | C_2H_5Cl name | hydrogen chloride | ethylene | chloroethane

| hydrogen chloride | ethylene | chloroethane molar mass | 36.46 g/mol | 28.054 g/mol | 64.51 g/mol phase | gas (at STP) | gas (at STP) | melting point | -114.17 °C | -169 °C | boiling point | -85 °C | -104 °C | density | 0.00149 g/cm^3 (at 25 °C) | 1.153 g/cm^3 (at 25 °C) | 0.765 g/cm^3 solubility in water | miscible | insoluble | surface tension | | 0.0181 N/m | dynamic viscosity | | 1.034×10^-5 Pa s (at 25 °C) |