Na2SiO3 = SiO2 + Na2O

Na_2SiO_3 sodium metasilicate ⟶ SiO_2 silicon dioxide + Na_2O sodium oxide

Balance the chemical equation algebraically: Na_2SiO_3 ⟶ SiO_2 + Na_2O Add stoichiometric coefficients, c_i, to the reactants and products: c_1 Na_2SiO_3 ⟶ c_2 SiO_2 + c_3 Na_2O Set the number of atoms in the reactants equal to the number of atoms in the products for Na, O and Si: Na: | 2 c_1 = 2 c_3 O: | 3 c_1 = 2 c_2 + c_3 Si: | c_1 = c_2 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_2SiO_3 ⟶ SiO_2 + Na_2O

⟶ +

sodium metasilicate ⟶ silicon dioxide + sodium oxide

Construct the equilibrium constant, K, expression for: Na_2SiO_3 ⟶ SiO_2 + Na_2O 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_2SiO_3 ⟶ SiO_2 + Na_2O 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_2SiO_3 | 1 | -1 SiO_2 | 1 | 1 Na_2O | 1 | 1 Assemble the activity expressions accounting for the state of matter and ν_i: chemical species | c_i | ν_i | activity expression Na_2SiO_3 | 1 | -1 | ([Na2SiO3])^(-1) SiO_2 | 1 | 1 | [SiO2] Na_2O | 1 | 1 | [Na2O] 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 = ([Na2SiO3])^(-1) [SiO2] [Na2O] = ([SiO2] [Na2O])/([Na2SiO3])

Construct the rate of reaction expression for: Na_2SiO_3 ⟶ SiO_2 + Na_2O 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_2SiO_3 ⟶ SiO_2 + Na_2O 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_2SiO_3 | 1 | -1 SiO_2 | 1 | 1 Na_2O | 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_2SiO_3 | 1 | -1 | -(Δ[Na2SiO3])/(Δt) SiO_2 | 1 | 1 | (Δ[SiO2])/(Δt) Na_2O | 1 | 1 | (Δ[Na2O])/(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[Na2SiO3])/(Δt) = (Δ[SiO2])/(Δt) = (Δ[Na2O])/(Δt) (assuming constant volume and no accumulation of intermediates or side products)

| sodium metasilicate | silicon dioxide | sodium oxide formula | Na_2SiO_3 | SiO_2 | Na_2O Hill formula | Na_2O_3Si | O_2Si | Na_2O name | sodium metasilicate | silicon dioxide | sodium oxide IUPAC name | disodium dioxido-oxosilane | dioxosilane | disodium oxygen(-2) anion

| sodium metasilicate | silicon dioxide | sodium oxide molar mass | 122.06 g/mol | 60.083 g/mol | 61.979 g/mol phase | solid (at STP) | solid (at STP) | melting point | 72.2 °C | 1713 °C | boiling point | | 2950 °C | density | 1.749 g/cm^3 | 2.196 g/cm^3 | 2.27 g/cm^3 solubility in water | soluble | insoluble | dynamic viscosity | 1 Pa s (at 1088 °C) | | odor | | odorless |