Cl2 + C2H4 = C2H4Cl2

Cl_2 chlorine + CH_2=CH_2 ethylene ⟶ ClCH_2CH_2Cl ethylene dichloride

Balance the chemical equation algebraically: Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cl_2 + c_2 CH_2=CH_2 ⟶ c_3 ClCH_2CH_2Cl Set the number of atoms in the reactants equal to the number of atoms in the products for Cl, C and H: Cl: | 2 c_1 = 2 c_3 C: | 2 c_2 = 2 c_3 H: | 4 c_2 = 4 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: | | Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl

+ ⟶

chlorine + ethylene ⟶ ethylene dichloride

Construct the equilibrium constant, K, expression for: Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl 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: Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl 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 Cl_2 | 1 | -1 CH_2=CH_2 | 1 | -1 ClCH_2CH_2Cl | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Cl_2 | 1 | -1 | ([Cl2])^(-1) CH_2=CH_2 | 1 | -1 | ([CH2=CH2])^(-1) ClCH_2CH_2Cl | 1 | 1 | [ClCH2CH2Cl] 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 = ([Cl2])^(-1) ([CH2=CH2])^(-1) [ClCH2CH2Cl] = ([ClCH2CH2Cl])/([Cl2] [CH2=CH2])

Construct the rate of reaction expression for: Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl 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: Cl_2 + CH_2=CH_2 ⟶ ClCH_2CH_2Cl 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 Cl_2 | 1 | -1 CH_2=CH_2 | 1 | -1 ClCH_2CH_2Cl | 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 Cl_2 | 1 | -1 | -(Δ[Cl2])/(Δt) CH_2=CH_2 | 1 | -1 | -(Δ[CH2=CH2])/(Δt) ClCH_2CH_2Cl | 1 | 1 | (Δ[ClCH2CH2Cl])/(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[Cl2])/(Δt) = -(Δ[CH2=CH2])/(Δt) = (Δ[ClCH2CH2Cl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| chlorine | ethylene | ethylene dichloride formula | Cl_2 | CH_2=CH_2 | ClCH_2CH_2Cl Hill formula | Cl_2 | C_2H_4 | C_2H_4Cl_2 name | chlorine | ethylene | ethylene dichloride IUPAC name | molecular chlorine | ethylene | 1, 2-dichloroethane

| chlorine | ethylene | ethylene dichloride molar mass | 70.9 g/mol | 28.054 g/mol | 98.95 g/mol phase | gas (at STP) | gas (at STP) | liquid (at STP) melting point | -101 °C | -169 °C | -35 °C boiling point | -34 °C | -104 °C | 83 °C density | 0.003214 g/cm^3 (at 0 °C) | 1.153 g/cm^3 (at 25 °C) | 1.256 g/cm^3 solubility in water | | insoluble | surface tension | | 0.0181 N/m | 0.03514 N/m dynamic viscosity | | 1.034×10^-5 Pa s (at 25 °C) | 7.79×10^-4 Pa s (at 25 °C)