Input interpretation
Cl_2 chlorine + Ag silver ⟶ AgCl silver chloride
Balanced equation
Balance the chemical equation algebraically: Cl_2 + Ag ⟶ AgCl Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Cl_2 + c_2 Ag ⟶ c_3 AgCl Set the number of atoms in the reactants equal to the number of atoms in the products for Cl and Ag: Cl: | 2 c_1 = c_3 Ag: | 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 2 c_3 = 2 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Cl_2 + 2 Ag ⟶ 2 AgCl
Structures
+ ⟶
Names
chlorine + silver ⟶ silver chloride
Reaction thermodynamics
Enthalpy
| chlorine | silver | silver chloride molecular enthalpy | 0 kJ/mol | 0 kJ/mol | -127 kJ/mol total enthalpy | 0 kJ/mol | 0 kJ/mol | -254 kJ/mol | H_initial = 0 kJ/mol | | H_final = -254 kJ/mol ΔH_rxn^0 | -254 kJ/mol - 0 kJ/mol = -254 kJ/mol (exothermic) | |
Entropy
| chlorine | silver | silver chloride molecular entropy | 223 J/(mol K) | 42.6 J/(mol K) | 96.3 J/(mol K) total entropy | 223 J/(mol K) | 85.2 J/(mol K) | 192.6 J/(mol K) | S_initial = 308.2 J/(mol K) | | S_final = 192.6 J/(mol K) ΔS_rxn^0 | 192.6 J/(mol K) - 308.2 J/(mol K) = -115.6 J/(mol K) (exoentropic) | |
Equilibrium constant
Construct the equilibrium constant, K, expression for: Cl_2 + Ag ⟶ AgCl 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 + 2 Ag ⟶ 2 AgCl 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 Ag | 2 | -2 AgCl | 2 | 2 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) Ag | 2 | -2 | ([Ag])^(-2) AgCl | 2 | 2 | ([AgCl])^2 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) ([Ag])^(-2) ([AgCl])^2 = ([AgCl])^2/([Cl2] ([Ag])^2)
Rate of reaction
Construct the rate of reaction expression for: Cl_2 + Ag ⟶ AgCl 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 + 2 Ag ⟶ 2 AgCl 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 Ag | 2 | -2 AgCl | 2 | 2 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) Ag | 2 | -2 | -1/2 (Δ[Ag])/(Δt) AgCl | 2 | 2 | 1/2 (Δ[AgCl])/(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) = -1/2 (Δ[Ag])/(Δt) = 1/2 (Δ[AgCl])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)
Chemical names and formulas
| chlorine | silver | silver chloride formula | Cl_2 | Ag | AgCl name | chlorine | silver | silver chloride IUPAC name | molecular chlorine | silver | chlorosilver
Substance properties
| chlorine | silver | silver chloride molar mass | 70.9 g/mol | 107.8682 g/mol | 143.32 g/mol phase | gas (at STP) | solid (at STP) | solid (at STP) melting point | -101 °C | 960 °C | 455 °C boiling point | -34 °C | 2212 °C | 1554 °C density | 0.003214 g/cm^3 (at 0 °C) | 10.49 g/cm^3 | 5.56 g/cm^3 solubility in water | | insoluble |
Units