MgO + CH3COOH = H2O + Mg(CH3COO)2

MgO magnesium oxide + CH_3CO_2H acetic acid ⟶ H_2O water + Mg(CH3COO)2

Balance the chemical equation algebraically: MgO + CH_3CO_2H ⟶ H_2O + Mg(CH3COO)2 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 MgO + c_2 CH_3CO_2H ⟶ c_3 H_2O + c_4 Mg(CH3COO)2 Set the number of atoms in the reactants equal to the number of atoms in the products for Mg, O, C and H: Mg: | c_1 = c_4 O: | c_1 + 2 c_2 = c_3 + 4 c_4 C: | 2 c_2 = 4 c_4 H: | 4 c_2 = 2 c_3 + 6 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_1 = 1 and solve the system of equations for the remaining coefficients: c_1 = 1 c_2 = 2 c_3 = 1 c_4 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | MgO + 2 CH_3CO_2H ⟶ H_2O + Mg(CH3COO)2

+ ⟶ + Mg(CH3COO)2

magnesium oxide + acetic acid ⟶ water + Mg(CH3COO)2

Construct the equilibrium constant, K, expression for: MgO + CH_3CO_2H ⟶ H_2O + Mg(CH3COO)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: MgO + 2 CH_3CO_2H ⟶ H_2O + Mg(CH3COO)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 MgO | 1 | -1 CH_3CO_2H | 2 | -2 H_2O | 1 | 1 Mg(CH3COO)2 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression MgO | 1 | -1 | ([MgO])^(-1) CH_3CO_2H | 2 | -2 | ([CH3CO2H])^(-2) H_2O | 1 | 1 | [H2O] Mg(CH3COO)2 | 1 | 1 | [Mg(CH3COO)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 = ([MgO])^(-1) ([CH3CO2H])^(-2) [H2O] [Mg(CH3COO)2] = ([H2O] [Mg(CH3COO)2])/([MgO] ([CH3CO2H])^2)

Construct the rate of reaction expression for: MgO + CH_3CO_2H ⟶ H_2O + Mg(CH3COO)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: MgO + 2 CH_3CO_2H ⟶ H_2O + Mg(CH3COO)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 MgO | 1 | -1 CH_3CO_2H | 2 | -2 H_2O | 1 | 1 Mg(CH3COO)2 | 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 MgO | 1 | -1 | -(Δ[MgO])/(Δt) CH_3CO_2H | 2 | -2 | -1/2 (Δ[CH3CO2H])/(Δt) H_2O | 1 | 1 | (Δ[H2O])/(Δt) Mg(CH3COO)2 | 1 | 1 | (Δ[Mg(CH3COO)2])/(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[MgO])/(Δt) = -1/2 (Δ[CH3CO2H])/(Δt) = (Δ[H2O])/(Δt) = (Δ[Mg(CH3COO)2])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| magnesium oxide | acetic acid | water | Mg(CH3COO)2 formula | MgO | CH_3CO_2H | H_2O | Mg(CH3COO)2 Hill formula | MgO | C_2H_4O_2 | H_2O | C4H6MgO4 name | magnesium oxide | acetic acid | water | IUPAC name | oxomagnesium | acetic acid | water |

| magnesium oxide | acetic acid | water | Mg(CH3COO)2 molar mass | 40.304 g/mol | 60.052 g/mol | 18.015 g/mol | 142.39 g/mol phase | solid (at STP) | liquid (at STP) | liquid (at STP) | melting point | 2852 °C | 16.2 °C | 0 °C | boiling point | 3600 °C | 117.5 °C | 99.9839 °C | density | 3.58 g/cm^3 | 1.049 g/cm^3 | 1 g/cm^3 | solubility in water | | miscible | | surface tension | | 0.0288 N/m | 0.0728 N/m | dynamic viscosity | | 0.001056 Pa s (at 25 °C) | 8.9×10^-4 Pa s (at 25 °C) | odor | odorless | vinegar-like | odorless |