Cl2 + C5H12 = HCl + C5H10Cl2

Cl_2 chlorine + CH_3(CH_2)_3CH_3 N-pentane ⟶ HCl hydrogen chloride + Cl(CH_2)_5Cl 1, 5-dichloropentane

Balance the chemical equation algebraically: Cl_2 + CH_3(CH_2)_3CH_3 ⟶ HCl + Cl(CH_2)_5Cl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cl_2 + c_2 CH_3(CH_2)_3CH_3 ⟶ c_3 HCl + c_4 Cl(CH_2)_5Cl 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 = c_3 + 2 c_4 C: | 5 c_2 = 5 c_4 H: | 12 c_2 = c_3 + 10 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 Cl_2 + CH_3(CH_2)_3CH_3 ⟶ 2 HCl + Cl(CH_2)_5Cl

+ ⟶ +

chlorine + N-pentane ⟶ hydrogen chloride + 1, 5-dichloropentane

Construct the equilibrium constant, K, expression for: Cl_2 + CH_3(CH_2)_3CH_3 ⟶ HCl + Cl(CH_2)_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: 2 Cl_2 + CH_3(CH_2)_3CH_3 ⟶ 2 HCl + Cl(CH_2)_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 Cl_2 | 2 | -2 CH_3(CH_2)_3CH_3 | 1 | -1 HCl | 2 | 2 Cl(CH_2)_5Cl | 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 | 2 | -2 | ([Cl2])^(-2) CH_3(CH_2)_3CH_3 | 1 | -1 | ([CH3(CH2)3CH3])^(-1) HCl | 2 | 2 | ([HCl])^2 Cl(CH_2)_5Cl | 1 | 1 | [Cl(CH2)5Cl] 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])^(-2) ([CH3(CH2)3CH3])^(-1) ([HCl])^2 [Cl(CH2)5Cl] = (([HCl])^2 [Cl(CH2)5Cl])/(([Cl2])^2 [CH3(CH2)3CH3])

Construct the rate of reaction expression for: Cl_2 + CH_3(CH_2)_3CH_3 ⟶ HCl + Cl(CH_2)_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: 2 Cl_2 + CH_3(CH_2)_3CH_3 ⟶ 2 HCl + Cl(CH_2)_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 Cl_2 | 2 | -2 CH_3(CH_2)_3CH_3 | 1 | -1 HCl | 2 | 2 Cl(CH_2)_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 Cl_2 | 2 | -2 | -1/2 (Δ[Cl2])/(Δt) CH_3(CH_2)_3CH_3 | 1 | -1 | -(Δ[CH3(CH2)3CH3])/(Δt) HCl | 2 | 2 | 1/2 (Δ[HCl])/(Δt) Cl(CH_2)_5Cl | 1 | 1 | (Δ[Cl(CH2)5Cl])/(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[Cl2])/(Δt) = -(Δ[CH3(CH2)3CH3])/(Δt) = 1/2 (Δ[HCl])/(Δt) = (Δ[Cl(CH2)5Cl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| chlorine | N-pentane | hydrogen chloride | 1, 5-dichloropentane formula | Cl_2 | CH_3(CH_2)_3CH_3 | HCl | Cl(CH_2)_5Cl Hill formula | Cl_2 | C_5H_12 | ClH | C_5H_10Cl_2 name | chlorine | N-pentane | hydrogen chloride | 1, 5-dichloropentane IUPAC name | molecular chlorine | pentane | hydrogen chloride | 1, 5-dichloropentane

| chlorine | N-pentane | hydrogen chloride | 1, 5-dichloropentane molar mass | 70.9 g/mol | 72.15 g/mol | 36.46 g/mol | 141 g/mol phase | gas (at STP) | liquid (at STP) | gas (at STP) | liquid (at STP) melting point | -101 °C | -129.67 °C | -114.17 °C | -72 °C boiling point | -34 °C | 36.06 °C | -85 °C | 64.5 °C (measured at 1333 Pa) density | 0.003214 g/cm^3 (at 0 °C) | 0.6262 g/cm^3 | 0.00149 g/cm^3 (at 25 °C) | 1.106 g/cm^3 solubility in water | | | miscible | insoluble surface tension | | 0.016 N/m | | dynamic viscosity | | 2.24×10^-4 Pa s (at 25 °C) | | 0.00159 Pa s (at 25 °C) odor | | gasoline-like | |