O2 + CO = CO2

O_2 (oxygen) + CO (carbon monoxide) ⟶ CO_2 (carbon dioxide)

Balance the chemical equation algebraically: O_2 + CO ⟶ CO_2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 O_2 + c_2 CO ⟶ c_3 CO_2 Set the number of atoms in the reactants equal to the number of atoms in the products for O and C: O: | 2 c_1 + c_2 = 2 c_3 C: | 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: | | O_2 + 2 CO ⟶ 2 CO_2

+ ⟶

oxygen + carbon monoxide ⟶ carbon dioxide

| oxygen | carbon monoxide | carbon dioxide molecular enthalpy | 0 kJ/mol | -110.5 kJ/mol | -393.5 kJ/mol total enthalpy | 0 kJ/mol | -221 kJ/mol | -787 kJ/mol | H_initial = -221 kJ/mol | | H_final = -787 kJ/mol ΔH_rxn^0 | -787 kJ/mol - -221 kJ/mol = -566 kJ/mol (exothermic) | |

| oxygen | carbon monoxide | carbon dioxide molecular free energy | 231.7 kJ/mol | -137 kJ/mol | -394.4 kJ/mol total free energy | 231.7 kJ/mol | -274 kJ/mol | -788.8 kJ/mol | G_initial = -42.3 kJ/mol | | G_final = -788.8 kJ/mol ΔG_rxn^0 | -788.8 kJ/mol - -42.3 kJ/mol = -746.5 kJ/mol (exergonic) | |

| oxygen | carbon monoxide | carbon dioxide molecular entropy | 205 J/(mol K) | 198 J/(mol K) | 214 J/(mol K) total entropy | 205 J/(mol K) | 396 J/(mol K) | 428 J/(mol K) | S_initial = 601 J/(mol K) | | S_final = 428 J/(mol K) ΔS_rxn^0 | 428 J/(mol K) - 601 J/(mol K) = -173 J/(mol K) (exoentropic) | |

Construct the equilibrium constant, K, expression for: O_2 + CO ⟶ CO_2 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: O_2 + 2 CO ⟶ 2 CO_2 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 O_2 | 1 | -1 CO | 2 | -2 CO_2 | 2 | 2 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression O_2 | 1 | -1 | ([O2])^(-1) CO | 2 | -2 | ([CO])^(-2) CO_2 | 2 | 2 | ([CO2])^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 = ([O2])^(-1) ([CO])^(-2) ([CO2])^2 = ([CO2])^2/([O2] ([CO])^2)

Construct the rate of reaction expression for: O_2 + CO ⟶ CO_2 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: O_2 + 2 CO ⟶ 2 CO_2 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 O_2 | 1 | -1 CO | 2 | -2 CO_2 | 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 O_2 | 1 | -1 | -(Δ[O2])/(Δt) CO | 2 | -2 | -1/2 (Δ[CO])/(Δt) CO_2 | 2 | 2 | 1/2 (Δ[CO2])/(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[O2])/(Δt) = -1/2 (Δ[CO])/(Δt) = 1/2 (Δ[CO2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| oxygen | carbon monoxide | carbon dioxide formula | O_2 | CO | CO_2 name | oxygen | carbon monoxide | carbon dioxide IUPAC name | molecular oxygen | carbon monoxide | carbon dioxide

| oxygen | carbon monoxide | carbon dioxide molar mass | 31.998 g/mol | 28.01 g/mol | 44.009 g/mol phase | gas (at STP) | gas (at STP) | gas (at STP) melting point | -218 °C | -205 °C | -56.56 °C (at triple point) boiling point | -183 °C | -191.5 °C | -78.5 °C (at sublimation point) density | 0.001429 g/cm^3 (at 0 °C) | 0.001145 g/cm^3 (at 25 °C) | 0.00184212 g/cm^3 (at 20 °C) surface tension | 0.01347 N/m | | dynamic viscosity | 2.055×10^-5 Pa s (at 25 °C) | 1.772×10^-5 Pa s (at 25 °C) | 1.491×10^-5 Pa s (at 25 °C) odor | odorless | odorless | odorless