Na2O + SO3 = Na2SO4

Na_2O sodium oxide + SO_3 sulfur trioxide ⟶ Na_2SO_4 sodium sulfate

Balance the chemical equation algebraically: Na_2O + SO_3 ⟶ Na_2SO_4 Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Na_2O + c_2 SO_3 ⟶ c_3 Na_2SO_4 Set the number of atoms in the reactants equal to the number of atoms in the products for Na, O and S: Na: | 2 c_1 = 2 c_3 O: | c_1 + 3 c_2 = 4 c_3 S: | 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 = 1 c_3 = 1 Substitute the coefficients into the chemical reaction to obtain the balanced equation: Answer: | | Na_2O + SO_3 ⟶ Na_2SO_4

+ ⟶

sodium oxide + sulfur trioxide ⟶ sodium sulfate

Construct the equilibrium constant, K, expression for: Na_2O + SO_3 ⟶ Na_2SO_4 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: Na_2O + SO_3 ⟶ Na_2SO_4 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 Na_2O | 1 | -1 SO_3 | 1 | -1 Na_2SO_4 | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Na_2O | 1 | -1 | ([Na2O])^(-1) SO_3 | 1 | -1 | ([SO3])^(-1) Na_2SO_4 | 1 | 1 | [Na2SO4] 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 = ([Na2O])^(-1) ([SO3])^(-1) [Na2SO4] = ([Na2SO4])/([Na2O] [SO3])

Construct the rate of reaction expression for: Na_2O + SO_3 ⟶ Na_2SO_4 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: Na_2O + SO_3 ⟶ Na_2SO_4 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 Na_2O | 1 | -1 SO_3 | 1 | -1 Na_2SO_4 | 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 Na_2O | 1 | -1 | -(Δ[Na2O])/(Δt) SO_3 | 1 | -1 | -(Δ[SO3])/(Δt) Na_2SO_4 | 1 | 1 | (Δ[Na2SO4])/(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[Na2O])/(Δt) = -(Δ[SO3])/(Δt) = (Δ[Na2SO4])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sodium oxide | sulfur trioxide | sodium sulfate formula | Na_2O | SO_3 | Na_2SO_4 Hill formula | Na_2O | O_3S | Na_2O_4S name | sodium oxide | sulfur trioxide | sodium sulfate IUPAC name | disodium oxygen(-2) anion | sulfur trioxide | disodium sulfate

| sodium oxide | sulfur trioxide | sodium sulfate molar mass | 61.979 g/mol | 80.06 g/mol | 142.04 g/mol phase | | liquid (at STP) | solid (at STP) melting point | | 16.8 °C | 884 °C boiling point | | 44.7 °C | 1429 °C density | 2.27 g/cm^3 | 1.97 g/cm^3 | 2.68 g/cm^3 solubility in water | | reacts | soluble dynamic viscosity | | 0.00159 Pa s (at 30 °C) |